BP_02 - 2001

24-1

Liquorice

Liquorice complies with the requirements of the 3rd edition of the European Pharmacopoeia for Liquorice Root[0277]. These requirements are reproduced after the heading Definition below.

Action and use Flavour.

PreparationsLiquorice Liquid Extract

When Powdered Liquorice is prescribed or demanded, material complying with the appropriaterequirements below shall be dispensed or supplied.

Ph Eur ___________________________________________________________________________________________________________

DEFINITION

Liquorice root consists of the dried unpeeled or peeled, whole or cut root and stolons of Glycyrrhizaglabra L. It contains not less than 4.0 per cent glycyrrhizic acid (C42H62O16, Mr 823), calculated withreference to the dried drug.

CHARACTERS

It has the macroscopic and microscopic characters described under Identification tests A and B.

IDENTIFICATION

A.The root has few branches. Its bark is brownish-grey to brown with longitudinal striations andbears traces of lateral roots. The cylindrical stolons are 1 cm to 2 cm in diameter; their externalappearance is similar to that of the root but there are occasional small buds. The fracture of the rootand the stolon is granular and fibrous. The cork layer is thin; the secondary phloem region is thickand light yellow with radial striations. The yellow xylem cylinder is compact, with a radiate structure.The stolon has a central pith, which is absent from the root. The external part of the bark is absentfrom the peeled root.

B.Reduce to a powder (355). The powder is light yellow to faintly greyish. Examine under amicroscope using chloral hydrate solution R. The powder shows fragments of yellow thick-walledfibres, 700 m to 1200 m long and 10 m to 20 m wide with a punctiform lumen, oftenaccompanied by crystal sheaths containing prisms of calcium oxalate 10 m to 35 m long and 2 mto 5 m wide. The walls of the large vessels are yellow, 5 m to 10 m thick lignified and havenumerous bordered pits with a slit-shaped aperture; fragments of cork consisting of thin-walled cellsand isolated prisms of calcium oxalate occur as well as fragments of parenchymatous tissue. Frag-ments of cork are absent from the peeled root. Examine under a microscope using a mixture of equalvolumes of glycerol R and water R. The powder shows simple, round or oval starch granules, 2 m to20 m in diameter.

C.Examine by thin-layer chromatography (2.2.27), using as the coating substance a suitable silica gelwith a fluorescent indicator having an optimal intensity at 254 nm.Test solution. To 0.50 g of the powdered drug (180) in a 50 ml round-bottomed flask add 16.0 ml ofwater R and 4.0 ml of hydrochloric acid R1 and heat on a water-bath under a reflux condenser for30 min. Cool and filter. Dry the filter and the round-bottomed flask at 105C for 60 min. Place thefilter in the round-bottomed flask, add 20.0 ml of ether R and heat in a water-bath at 40C under areflux condenser for 5 min. Cool and filter. Evaporate the filtrate to dryness. Dissolve the residue in5.0 ml of ether R.Reference solution. Dissolve 5.0 mg of glycyrrhetic acid R and 5.0 mg of thymol R in 5.0 ml of ether R.

Apply separately to the plate as bands 10 l of each solution. Develop over a path of 15 cm using amixture of 1 volume of concentrated ammonia R, 9 volumes of water R, 25 volumes of alcohol R and 65volumes of ethyl acetate R. Allow the plate to dry in air for 5 min and examine in ultraviolet light at254 nm. The chromatograms obtained with the test solution and with the reference solution show inthe lower half a quenching zone due to glycyrrhetic acid. Spray the plate with anisaldehyde solution R,and heat at 100C to 105C for 5 min to 10 min. Examine in daylight. The chromatogram obtainedwith the reference solution shows in the lower half the violet zone of glycyrrhetic acid and in theupper third the red zone of thymol. The chromatogram obtained with the test solution shows in thelower half of violet zone corresponding to the zone of glycyrrhetic acid in the chromatogram obtainedwith the reference solution and a yellow zone (isoliquiridigenine) in the upper third under the zone ofthymol in the chromatogram obtained with the reference solution. Further zones may be present.

TESTS

Loss on drying (2.2.32). Not more than 10.0 per cent, determined on 1.000 g of powdered drug(355) by drying in an oven at 100C to 105C for 2 h.

Total ash (2.4.16). Not more than 10.0 per cent for the unpeeled drug and not more than 6.0 percent for the peeled drug.

24-2

Ash insoluble in hydrochloric acid (2.8.1). Not more than 2.0 per cent for the unpeeled drug andnot more than 0.5 per cent for the peeled drug.

ASSAY

Examine by liquid chromatography (2.2.29).Test solution. Place 1.000 g of the powdered drug (180) in a 150 ml ground glass conical flask. Add100.0 ml of an 8 g/l solution of ammonia R and treat in a ultrasonic bath for 30 min. Centrifuge apart of the supernatant layer and dilute 1.0 ml to 5.0 ml with the same solvent. Filter the solutionthrough a filter (0.45 m) and use the filtrate as the test solution.

Stock solution. Dissolve 0.130 g of monoammonium glycyrrhizate CRS in an 8 g/l solution of ammonia Rand dilute to 100.0 ml with the same solvent.Reference solution (a). Dilute 5.0 ml of the stock solution to 100.0 ml with an 8 g/l solution ofammonia R.Reference solution (b). Dilute 10.0 ml of the stock solution to 100.0 ml with an 8 g/l solution ofammonia R.Reference solution (c). Dilute 15.0 ml of the stock solution to 100.0 ml with an 8 g/l solution ofammonia R.

The chromatographic procedure may be carried out using: a stainless steel column 0.10 m long and 4 mm in internal diameter packed with octadecylsilyl

silica gel for chromatography R (5 m), as mobile phase at a flow rate of 1.5 ml/min a mixture of 6 volumes of acetic acid R, 30 volumes

of acetonitrile R and 64 volumes of water R, as detector a spectrophotometer set at 254 nm, a 10 l loop injector.

Inject reference solution (c). Adjust the sensitivity of the system so that the height of the peaks areat least 50 per cent of the full scale of the recorder. Inject each reference solution and determine thepeak areas.

Establish a calibration curve with the concentration of the reference solutions (g/100 ml) as theabscissa and the corresponding areas as the ordinate.

Inject the test solution. Using the retention time and the peak area determined from the chromato-grams obtained with the reference solutions, locate and integrate the peak due to glycyrrhizic acid inthe chromatogram obtained with the test solution.

Calculate the percentage content of glycyrrhizic acid from the expression:

8408225

Bm

A

A =concentration of monoammonium glycyrrhizate in the test solution determined from thecalibration curve in g/100 ml,

B=declared percentage content of monoammonium glycyrrhizate CRS,m =mass of the drug in grams,

822 =molecular weight of glycyrrhizic acid,840 =molecular weight of the monoammonium glycyrrhizate (without any water of crystallisa-

tion).

STORAGE

Store in a well-closed container, protected from light.

LABELLING

The label states whether the drug is peeled or unpeeled.__________________________________________________________________________________________________________ Ph Eur

24-3

Lisinopril Dihydrate

1/01

H

N

O

H2N

HOOC H

NCOOHH

H

C21H31N3O5,2H2O 441.5 83915-83-7

Lisinopril Dihydrate complies with the requirements of the 3rd edition of the European Pharmacopoeia [1120].These requirements are reproduced after the heading Definition below.

Action and use Angiotensin-converting enzyme inhibitor.

PreparationLisinopril Tablets

Ph Eur ___________________________________________________________________________________________________________

DEFINITION

Lisinopril dihydrate contains not less than 98.5 per cent and not more than the equivalent of101.5 per cent of N-[N-[(1S)-1-carboxy-3-phenylpropyl]-L-lysyl]-L-proline, calculated with referenceto the anhydrous substance.

CHARACTERS

A white, crystalline powder, soluble in water, sparingly soluble in methanol, practically insoluble inacetone and in ethanol.

IDENTIFICATION

Examine by infrared absorption spectrophotometry (2.2.24), comparing with the spectrum obtainedwith lisinopril dihydrate CRS. Examine the substances prepared as discs.

TESTS

Specific optical rotation (2.2.7). Dissolve 0.5 g in zinc acetate solution R and dilute to 50.0 ml withthe same solvent. The specific optical rotation is 43 to 47, calculated with reference to theanhydrous substance.

Related substances Examine by liquid chromatography (2.2.29).

Test solution. Dissolve 20.0 mg of the substance to be examined in mobile phase A and dilute to10.0 ml with the same mobile phase.

Reference solution (a). Dissolve 20.0 mg of lisinopril dihydrate for performance test CRS in mobile phaseA and dilute to 10.0 ml with the same mobile phase.

Reference solution (b). Dilute 0.5 ml of the test solution to 50.0 ml with mobile phase A.

The chromatographic procedure may be carried out using: a stainless steel column 0.25 m long and 4.6 mm in internal diameter packed with octylsilyl silica

gel for chromatography R, as mobile phase at a flow rate of 1.8 ml/min:

Mobile phase A. Prepare a mixture of 30 volumes of acetonitrile R and 970 volumes of a 3.12 g/lsodium dihydrogen phosphate R solution adjusted to pH 5.0 with a 50 g/l solution of sodiumhydroxide R,Mobile phase B. Prepare a mixture of 200 ml of acetonitrile R and 800 ml of a 3.12 g/l sodiumdihydrogen phosphate R solution adjusted to pH 5.0 with a 50 g/l solution of sodium hydroxide R,

Time(min)

Mobile phase A(per cent V/V)

Mobile phase B(per cent V/V)

Comment

0 35 100 70 0 30 Linear gradient

35 45 70 30 Isocratic45 50 70 100 30 0 Switch to initial

eluent composition50 = 0 100 0 Restart gradient

24-4

as detector a spectrophotometer set at 210 nm,maintaining the temperature of the column at 50C.

Equilibrate the column with mobile phase A for at least 30 min. Adjust the sensitivity of thesystem so that the height of the principal peak in the chromatogram obtained with 20 l of refer-ence solution (b) is at least 50 per cent of the full scale of the recorder.

Inject 20 l of reference solution (a). The resulting chromatogram resembles that of thespecimen chromatogram supplied with lisinopril dihydrate for performance test CRS in that the peaksdue to impurity A and impurity E fall on either side of the peak due to lisinopril. Measure theheights A1 and A2 above the baseline of the peaks due to impurity A and impurity E and the heightsB1 and B2 above the baseline of the lowest points of the curve separating these peaks from the peakdue to lisinopril. The test is not valid unless A1 is greater than nine times B1 and A2 is greater thannine times B2.

If necessary, adjust the pH of the mobile phase to 4.5 with phosphoric acid R and repeat thechromatography. A further adjustment to pH 4.0 may be necessary with some columns beforesatisfactory separation of impurity A, lisinopril and impurity E is obtained. If, after adjustment, theretention time of the peak due to impurities C and D becomes extended to the point where integra-tion becomes difficult, increase the content of mobile phase B from 30 per cent to 40 per cent overthe interval from 35 min to 45 min from the start of the chromatogram. Maintain this concentra-tion for a further 10 min. Return the concentration of mobile phase A to 100 per cent over thenext 10 min prior to the next injection.

Inject 20 l of the test solution and 20 l of reference solution (b). In the chromatogramobtained with the test solution: the area of any peak due to impurity E is not greater than 0.3 timesthe area of the principal peak in the chromatogram obtained with reference solution (b) (0.3 percent); the area of any peak, apart from the principal peak and any peak due to impurity E, is notgreater than 0.3 times the area of the principal peak in the chromatogram obtained with referencesolution (b) (0.3 per cent) and the sum of the areas of all such peaks is not greater than half thearea of the principal peak in the chromatogram obtained with reference solution (b) (0.5 per cent).Disregard any peak due to the solvent, any peak occurring in the first 3 minutes and any peak withan area less than 0.05 times the area of the principal peak in the chromatogram obtained withreference solution (b).

Water (2.5.12). 8.0 to 9.5 per cent, determined on 0.200 g by the semi-micro determination ofwater.

Sulphated ash (2.4.14). Not more than 0.1 per cent, determined on 1.0 g.

ASSAY

Dissolve 0.350 g in 50 ml of distilled water R. Titrate with 0.1M sodium hydroxide, determining theend-point potentiometrically (2.2.20).

1 ml of 0.1M sodium hydroxide is equivalent to 40.55 mg of C21H31N3O5.

IMPURITIES

NH2

HHOOC

and enantiomer

A. (RS)-2-amino-4-phenylbutanoic acid,

Me

SO3H

B. toluene-4-sulphonic acid,

N

HHOOC

NO

O

H

NH2H

C. (S)-2-[(3S,8aS)-3-(4-aminobutyl)-1,4-dioxo-1,2,3,4,6,7,8,8a-octahydropyrrolo[1,2-a]piperazin-2-yl]-4-phenylbutanoic acid ((S,S,S)-diketopiperazine),

N

HHOOC

NO

O

H

NH2H

D. (S)-2-[(3S,8aR)-3-(4-aminobutyl)-1,4-dioxo-1,2,3,4,6,7,8,8a-octahydropyrrolo[1,2-a]piperazin-2-yl]-4-phenylbutanoic acid ((R,S,S)-diketopiperazine),

24-5

NNH

H

H2N

H

COOHH

HOOC

O

E. N-[N-[(R)-1-carboxy-3-phenylpropyl)-L-lysyl]-L-proline (lisinopril (R,S,S)-isomer),

NNH

H

H2N

H

COOHH

HOOC

O

F. N-[N-[(S)-1-carboxy-3-cyclohexylpropyl)-L-lysyl]-L-proline (cyclohexyl analogue).__________________________________________________________________________________________________________ Ph Eur

24-6

Lithium Carbonate

Li2CO3 73.9 554-13-2

Lithium Carbonate complies with the requirements of the 3rd edition of the European Pharmacopoeia [0228].These requirements are reproduced after the heading Definition below.

Action and use Prophylaxis of affective disorders.

PreparationsLithium Carbonate TabletsSlow Lithium Carbonate Tablets

Ph Eur ___________________________________________________________________________________________________________

DEFINITION

Lithium carbonate contains not less than 98.5 per cent and not more than the equivalent of100.5 per cent of Li2CO3.

CHARACTERS

A white powder, slightly soluble in water, practically insoluble in alcohol.

IDENTIFICATION

A. When moistened with hydrochloric acid R, it gives a red colour to a non-luminous flame.

B. Dissolve 0.2 g in 1 ml of hydrochloric acid R. Evaporate to dryness on a water-bath. The residuedissolves in 3 ml of alcohol R.

C. It gives the reaction of carbonates (2.3.1).

TESTS

Solution S Suspend 10.0 g in 30 ml of distilled water R and dissolve by the addition of 22 ml of nitricacid R. Add dilute sodium hydroxide solution R until the solution is neutral and dilute to 100 ml withdistilled water R.

Appearance of solution Solution S is clear (2.2.1) and colourless (Method II, 2.2.2).

Chlorides (2.4.4). 2.5 ml of solution S diluted to 15 ml with water R complies with the limit test forchlorides (200 ppm).

Sulphates (2.4.13). Disperse 1.25 g in 5 ml of distilled water R and dissolve by adding 5 ml of hydro-chloric acid R1. Boil for 2 min. Cool and add dilute sodium hydroxide solution R until neutral. Dilute to25 ml with distilled water R. The solution complies with the limit test for sulphates (200 ppm).

Arsenic (2.4.2). 0.5 g complies with limit test A for arsenic (2 ppm).

Calcium (2.4.3). 5 ml of solution S diluted to 15 ml with distilled water R complies with the limit testfor calcium (200 ppm).

Heavy metals (2.4.8). 12 ml of solution S complies with limit test A for heavy metals (20 ppm).Prepare the standard using lead standard solution (2 ppm Pb) R.

Iron (2.4.9). 5 ml of solution S diluted to 10 ml with water R complies with the limit test for iron(20 ppm).

Magnesium (2.4.6). Dilute 1 ml of solution S to 10 ml with water R. 6.7 ml of this solution dilutedto 10 ml with water R complies with the limit test for magnesium (150 ppm).

Potassium Not more than 300 ppm of K, determined by atomic emission spectrometry (Method I,2.2.22).

Test solution. Dissolve 1.0 g of the substance to be examined in 10 ml of hydrochloric acid R1 anddilute to 50.0 ml with water R.

Reference solutions. Prepare the reference solutions using a solution of potassium chloride R containing500 g of K per millilitre, diluted as required.

Measure the emission intensity at 766.5 nm.

Sodium Not more than 300 ppm of Na, determined by atomic emission spectrometry (Method I,2.2.22).

Test solution. Dissolve 1.0 g of the substance to be examined in 10 ml of hydrochloric acid R1 anddilute to 50.0 ml with water R.

Reference solutions. Prepare the reference solutions using a solution of sodium chloride R containing500 g of Na per millilitre, diluted as required.

Measure the emission intensity at 589 nm.

24-7

ASSAY

Dissolve 0.500 g in 25.0 ml of 1M hydrochloric acid. Titrate with 1M sodium hydroxide, using methylorange solution R as indicator.

1 ml of 1M hydrochloric acid is equivalent to 36.95 mg of Li2CO3.__________________________________________________________________________________________________________ Ph Eur

24-8

Lithium Citrate

HO C

CH2COOLi

CH2COOLi

COOLi

C6H5Li3O7,4H2O 282.0 6080-58-6

Lithium Citrate complies with the requirements of the 3rd edition of the European Pharmacopoeia [0621].These requirements are reproduced after the heading Definition below.

Action and use Antidepressant.

PreparationLithium Citrate Oral Solution

Ph Eur ___________________________________________________________________________________________________________

DEFINITION

Lithium citrate contains not less than 98.0 per cent and not more than the equivalent of 102.0 percent of trilithium 2-hydroxypropane-1,2,3-tricarboxylate, calculated with reference to the anhydroussubstance.

CHARACTERS

A white or almost white, fine crystalline powder, freely soluble in water, slightly soluble in alcohol.

IDENTIFICATION

A. When moistened with hydrochloric acid R, it gives a red colour to a non-luminous flame.

B. Dilute 3 ml of solution S (see Tests) to 10 ml with water R. Add 3 ml of potassium ferriperiodatesolution R. A white or yellowish-white precipitate is formed.

C. To 1 ml of solution S add 4 ml of water R. The solution gives the reaction of citrates (2.3.1).

TESTS

Solution S Dissolve 10.0 g in carbon dioxide-free water R prepared from distilled water R and dilute to100 ml with the same solvent.

Appearance of solution Solution S is clear (2.2.1) and colourless (Method II, 2.2.2).

Acidity or alkalinity To 10 ml of solution S add 0.1 ml of phenolphthalein solution R. Not more than0.2 ml of 0.1M hydrochloric acid or 0.1M sodium hydroxide is required to change the colour of theindicator.

Readily carbonisable substances To 0.20 g of the powdered substance to be examined add 10 mlof sulphuric acid R and heat in a water-bath at 90 1C for 60 min. Cool rapidly. The solution is notmore intensely coloured than reference solution Y2 or GY2 (Method II, 2.2.2).

Chlorides (2.4.4). Dilute 5 ml of solution S to 15 ml with water R. The solution complies with thelimit test for chlorides (100 ppm).

Oxalates Dissolve 0.50 g in 4 ml of water R, add 3 ml of hydrochloric acid R and 1 g of granulatedzinc R and heat on a water-bath for 1 min. Allow to stand for 2 min, decant the liquid into a test-tubecontaining 0.25 ml of a 10 g/l solution of phenylhydrazine hydrochloride R and heat to boiling. Coolrapidly, transfer to a graduated cylinder and add an equal volume of hydrochloric acid R and 0.25 mlof potassium ferricyanide solution R. Shake and allow to stand for 30 min. Any pink colour in thesolution is not more intense than that in a standard prepared at the same time and in the samemanner using 4 ml of a 0.05 g/l solution of oxalic acid R (300 ppm, calculated as anhydrous oxalateion).

Sulphates (2.4.13). To 3 ml of solution S add 2 ml of hydrochloric acid R1 and dilute to 17 ml withdistilled water R. The solution complies with the limit test for sulphates (500 ppm). Prepare thestandard using 15 ml of a mixture of 2 ml of hydrochloric acid R1 and 15 ml of sulphate standardsolution (10 ppm SO4) R and compare the opalescence after 15 min.


Water (2.5.12). 24.0 per cent to 27.0 per cent, determined on 0.100 g by the semi-micro determina-tion of water. After adding the substance to be examined, stir for 15 min before titrating. Carry out ablank titration.

24-9

ASSAY

Dissolve 80.0 mg in 50 ml of anhydrous acetic acid R, heating to about 50C. Allow to cool. Titratewith 0.1M perchloric acid, using 0.25 ml of naphtholbenzein solution R as indicator, until the colourchanges from yellow to green.

1 ml of 0.1M perchloric acid is equivalent to 7.00 mg of C6H5Li3O7.

STORAGE

Store in an airtight container.__________________________________________________________________________________________________________ Ph Eur

24-10

Lofepramine Hydrochloride

N

N

OMe

Cl,HCl

C26H27ClN2O,HCl 455.4 26786-32-3

Definition Lofepramine Hydrochloride is 5-(3-[N-(4-chlorophenacyl)-N-methylamino]propyl)-10,11-dihydro-5H-dibenz[b,f]azepine hydrochloride. It contains not less than 98.5% and not morethan 101.0% of C26H27ClN2O,HCl, calculated with reference to the dried substance.

Characteristics A fine, yellowish white to greenish yellow powder with a faint characteristic odour.Very soluble in ethanol (96%) and in methanol; slightly soluble in acetone; very slightly soluble in

water.It exhibits polymorphism.

IdentificationA. The infrared absorption spectrum, Appendix II A, is concordant with the reference spectrum oflofepramine hydrochloride (form A) (RS 399A).

B. 2 ml of a 1% w/v solution in ethanol (96%) complies with the test for chlorides, Appendix VI.

Related substances Carry out the method for liquid chromatography, Appendix III D, using thefollowing solutions. Solution (1) contains 0.1% w/v of the substance being examined in the mobilephase. For solution (2) dilute 1 volume of solution (1) to 200 volumes with the mobile phase.Solution (3) contains 0.0002% w/v each of desipramine hydrochloride EPCRS and imipramine hydro-chloride EPCRS in the mobile phase.

Inject 20 l of solutions (1) and (2). Inject 20 l of solution (3) and allow the chromatography tocontinue for 4 times the retention time of the principal peak.

The chromatographic procedure may be carried out using (a) a stainless steel column (25 cm 4.6 mm) packed with base-deactivated end-capped octylsilyl silica gel for chromatography (5 m)(Lichrospher 60 RP-select B is suitable) maintained at 50, (b) as the mobile phase with a flow rateof 1.5 ml per minute a 0.9% w/v solution of sodium dodecyl sulphate in a mixture of 550 volumes ofacetonitrile, 325 volumes of water and 125 volumes of a buffer solution of pH 1.0 containing 0.015%w/v of glycine, 0.018% w/v of sodium chloride and 0.44% w/v of hydrochloric acid and (c) a detectionwavelength of 254 nm.

The test is not valid unless, in the chromatogram obtained with solution (3), the resolution factorbetween the two principal peaks is at least 0.9.

In the chromatogram obtained with solution (1) the area of any secondary peak is not greater thanthe area of the peak in the chromatogram obtained with solution (2) (0.5%) and the sum of the areasof any secondary peaks is not greater than twice the area of the peak in the chromatogram obtainedwith solution (2) (1%).

Loss on drying When dried at a temperature of 100 at a pressure not exceeding 0.2 kPa, loses notmore than 0.5% of its weight. Use 1 g.

Assay Carry out the method for liquid chromatography, Appendix III D, using the following solutions.Solution (1) contains 0.02% w/v of the substance being examined in the mobile phase. Solution (2)contains 0.02% w/v of lofepramine hydrochloride BPCRS in the mobile phase.

The chromatographic procedure described under the test for Related substances may be used.Inject 20 l of each solution.Calculate the content of C26H27ClN2O,HCl from the chromatograms obtained and using the

declared content of C26H27ClN2O,HCl in lofepramine hydrochloride BPCRS.

Storage Lofepramine Hydrochloride should be kept in an airtight container and protected fromlight.

Action and use Antidepressant.

PreparationLofepramine Tablets

24-11

IMPURITIES

Cl

eHNO

A. 1-methylamino-4-chloroacetophenone,

Cl

HOOCB. 4-chlorobenzoic acid,

N

NHMeC. desipramine,

NH

D. iminodibenzyl,

N

NCHO

MeE. N-formyldesipramine,

Cl

ON

N

O

Cl

MeBr

F. N,N-bis(4-chlorophenacyl)desipramine bromide,

N

NMe2G. imipramine,

Cl

r

OH. 2-bromo-4-chloroacetophenone.

24-12

Lomustine

N NCl

O

NOH

C9H16ClN3O2 233.7 13010-47-4

Lomustine complies with the requirements of the 3rd edition of the European Pharmacopoeia [0928]. Theserequirements are reproduced after the heading Definition below.

Action and use Cytotoxic.

PreparationLomustine Capsules

Ph Eur ___________________________________________________________________________________________________________

DEFINITION

Lomustine contains not less than 98.5 per cent and not more than the equivalent of 100.5 per cent of1-(2-chloroethyl)-3-cyclohexyl-1-nitrosourea, calculated with reference to the dried substance.

CHARACTERS

A yellow, crystalline powder, practically insoluble in water, freely soluble in acetone and in methylenechloride, soluble in alcohol.

Carry out the tests protected from light and prepare all the solutions immediately before use.

IDENTIFICATION

First identification: C.Second identification: A, B, D, E.

A. Melting point (2.2.14): 89C to 91C.

B. Dissolve 50.0 mg in alcohol R and dilute to 50.0 ml with the same solvent. Dilute 2.0 ml to100.0 ml with alcohol R. Examined between 220 nm and 350 nm (2.2.25), the solution shows anabsorption maximum at 230 nm. The specific absorbance at the maximum is 250 to 270.

C. Examine by infrared absorption spectrophotometry (2.2.24), comparing with the spectrumobtained with lomustine CRS. Examine the substances prepared as discs.

D. Examine the chromatograms obtained in the test for related substances. The principal spot in thechromatogram obtained with test solution (b) is similar in position, colour and size to the principalspot in the chromatogram obtained with reference solution (a).

E. Dissolve about 25 mg in 1 ml of methanol R, add 0.1 ml of dilute sodium hydroxide solution R and2 ml of water R. Acidify by adding dropwise dilute nitric acid R. Filter. The filtrate gives reaction (a) ofchlorides (2.3.1).

TESTS

Related substances

A. Examine by thin-layer chromatography (2.2.27), using silica gel G R as the coating substance.

Test solution (a). Dissolve 0.25 g of the substance to be examined in methanol R and dilute to 10 mlwith the same solvent.

Test solution (b). Dilute 1 ml of test solution (a) to 25 ml with methanol R.

Reference solution (a). Dissolve 10 mg of lomustine CRS in methanol R and dilute to 10 ml with thesame solvent.

Reference solution (b). Dilute 1 ml of test solution (b) to 10 ml with methanol R.

Reference solution (c). Dilute 1 ml of test solution (b) to 20 ml with methanol R.

Reference solution (d). Dissolve 10 mg of lomustine CRS and 10 mg of dicyclohexylurea R in methanol Rand dilute to 10 ml with the same solvent.

Apply separately to the plate 5 l of each solution. Develop over a path of 15 cm using a mixture of20 volumes of glacial acetic acid R and 80 volumes of toluene R. Dry the plate at 110C for 1 h. At thebottom of a chromatography tank, place an evaporating dish containing a mixture of 1 volume ofhydrochloric acid R1, 1 volume of water R and 2 volumes of a 15 g/l solution of potassiumpermanganate R, close the tank and allow to stand for 15 min. Place the dried plate in the tank and

24-13

close the tank. Leave the plate in contact with the chlorine vapour for 5 min. Withdraw the plateand place it in a current of cold air until the excess of chlorine is removed and an area of coatingbelow the points of application does not give a blue colour with a drop of potassium iodide and starchsolution R. Spray with potassium iodide and starch solution R. Any spot in the chromatogram obtainedwith test solution (a), apart from the principal spot, is not more intense than the spot in the chrom-atogram obtained with reference solution (b) (0.4 per cent) and at most one such spot is moreintense than the spot in the chromatogram obtained with reference solution (c) (0.2 per cent). Thetest is not valid unless the chromatogram obtained with reference solution (d) shows two clearlyseparated principal spots.

B. Examine by liquid chromatography (2.2.29).

Test solution. Dissolve 0.25 g of the substance to be examined in methanol R and dilute to 10.0 ml thesame solvent.

Reference solution. Dilute 1.0 ml of the test solution to 100.0 ml with methanol R.

The chromatographic procedure may be carried out using: a stainless steel column 0.25 m long and 4 mm in internal diameter packed with octadecylsilyl

silica gel for chromatography R (5 m to 10 m), as mobile phase at a flow rate of 2 ml per minute a mixture of 50 volumes of methanol R and 50

volumes of water R, as detector a spectrophotometer set at 230 nm, a loop injector.

Inject 20 l of the reference solution. Adjust the sensitivity of the system so that the height of theprincipal peak in the chromatogram obtained with the reference solution is at least 50 per cent of thefull scale of the recorder. Inject separately 20 l of each solution. In the chromatogram obtained withthe test solution, the sum of the areas of any peaks apart from the principal peak is not greater thanthe area of the principal peak in the chromatogram obtained with the reference solution (1 per cent).Disregard any peak due to the solvent and any peak with an area less than 0.05 times that of theprincipal peak in the chromatogram obtained with the reference solution.

Chlorides (2.4.4). Dissolve 0.24 g in 4 ml of methanol R and add 20 ml of water R. Allow to standfor 20 min and filter. To 10 ml of the filtrate, add 5 ml of methanol R. The solution complies with thelimit test for chlorides (500 ppm). When preparing the standard, replace the 5 ml of water R with5 ml of methanol R.

Loss on drying (2.2.32). Not more than 1.0 per cent, determined on 1.000 g by drying in adesiccator over diphosphorus pentoxide R at a pressure not exceeding 0.7 kPa for 24 h.

ASSAY

Dissolve 0.200 g in about 3 ml of alcohol R and add 20 ml of a 200 g/l solution of potassiumhydroxide R and boil under a reflux condenser for 2 h. Add 75 ml of water R and 4 ml of nitric acid R.Cool and titrate with 0.1M silver nitrate, determining the end-point potentiometrically (2.2.20). Carryout a blank titration.

1 ml of 0.1M silver nitrate is equivalent to 23.37 mg of C9H16ClN3O2.

STORAGE


IMPURITIES

Cl N N ClO

H H

A. 1,3-bis(2-chloroethyl)urea,

N NCl

O

H H

B. 1-(2-chloroethyl)-3-cyclohexylurea,

N N

O

H H

C. 1,3-dicyclohexylurea.__________________________________________________________________________________________________________ Ph Eur

24-14

Loosestrife

1/01

Loosestrife complies with the requirements of the 3rd edition of the European Pharmacopoeia [1537]. Theserequirements are reproduced after the heading Definition below.

Ph Eur ___________________________________________________________________________________________________________

DEFINITION

Loosestrife consists of the dried flowering tops, whole or cut, of Lythrum salicaria L. It contains notless than 5.0 per cent of tannins, expressed as pyrogallol (C6H6O3; Mr 126.1) and calculated withreference to the dried drug.

CHARACTERS

It has the macroscopic and microscopic characters described under identification tests A and B.

IDENTIFICATION

A. The stems are rigid, four-angled, branching at the top, brownish-green, longitudinally wrinkledand pubescent. The leaves are opposite, decussate, rarely verticillate in threes and sometimesalternate at the inflorescence which forms a long terminal spike. The leaves are sessile, lanceolate andcordate at the base, 5 cm to 15 cm long and 1 cm to 2.5 cm wide, pubescent on the lower surface;the subsidiary veins form arcs that anastomose near the leaf margin. The flowers have a pubescent,tubular, persistent gamosepalous calyx, 4 mm to 8 mm long, consisting of 6 sepals bearing 6 small,triangular teeth alternating with 6 large acute teeth at least half as long as the tube; a polypetalouscorolla consisting of 6 violet-pink petals, each expanded at the top with a wavy outline and narrowingat the base. The androecium consists of 2 verticils of 6 stamens (one verticil with short, barelyemerging stamens, the other with long stamens extending well out of the corolla). The fruit, ifformed, is a small capsule included in the persistent calyx.

B. Reduce to a powder (355). The powder is greenish-yellow. Examine under a microscope usingchloral hydrate solution R. The powder shows unicellular or bicellular, uniseriate, thick-walled, finelypitted covering trichomes from the lower epidermis of the stem and leaf; numerous uniseriate,unicellular or bicellular, thin-walled, finely pitted covering trichomes from the calyx; transparentviolet-pink fragments from the petals; numerous cluster crystals of calcium oxalate; pollen grains with3 pores and a thin and slightly granular exine; fragments of the upper epidermis with large polygonalcells and sinuous walls; fragments of the lower epidermis with smaller polygonal cells and anomocyticstomata (2.8.3).

C. Examine by thin-layer chromatography (2.2.27), using a TLC silica gel plate R.

Test solution. To 1.0 g of the powdered drug (355) add 10 ml of methanol R and heat in a water-bathat 65C for 5 min with frequent shaking. Cool and filter. Dilute the filtrate to 10 ml with methanol R.

Reference solution. Dissolve 0.5 mg of chlorogenic acid R, 1 mg of hyperoside R, 1 mg of rutin R and1 mg of vitexin R in 10 ml of methanol R.

Apply to the plate as bands 10 l of each solution. Develop over a path of 15 cm using a mixture of7.5 volumes of anhydrous acetic acid R, 7.5 volumes of anhydrous formic acid R, 18 volumes of water Rand 67 volumes of ethyl acetate R. Dry the plate at 100C to 105C and spray it while still warm witha 10 g/l solution of diphenylboric acid aminoethyl ester R in methanol R. Subsequently spray the platewith a 50 g/l solution of macrogol 400 R in methanol R. Allow the plate to dry in air for 30 min andexamine in ultraviolet light at 365 nm. The chromatogram obtained with the reference solutionshows in the lower third a yellowish-brown fluorescent zone (rutin) and in the middle third a lightblue fluorescent zone (chlorogenic acid), above it a yellowish-brown fluorescent zone (hyperoside)and a green fluorescent zone (vitexin). The chromatogram obtained with the test solution shows abright green fluorescent zone slightly above the rutin zone in the chromatogram obtained with thereference solution, a yellow fluorescent zone similar in position to the chlorogenic acid zone in thechromatogram obtained with the reference solution, a yellow fluorescent zone similar in position tothe hyperoside zone in the chromatogram obtained with the reference solution and a bright greenfluorescent zone corresponding to the vitexin zone in the chromatogram obtained with the referencesolution.

TESTS

Foreign matter (2.8.2). It complies with the test for foreign matter.

Loss on drying (2.2.32). Not more than 12.0 per cent, determined on 1.000 g of the powdered drug(355) by drying in an oven at 100C to 105C.

Total ash (2.4.16). Not more than 7.0 per cent.

24-15

ASSAY

Carry out the determination of tannins in herbal drugs (2.8.14). Use 0.750 g of the powdered drug(180).

STORAGE

Store protected from light.__________________________________________________________________________________________________________ Ph Eur

24-16

Loperamide Hydrochloride

NNMe2

Ph Ph

O

OH

Cl

,HCl

C29H33ClN2O2,HCl 513.5 34552-83-5

Loperamide Hydrochloride complies with the requirements of the 3rd edition of the European Pharmacopoeia[0929]. These requirements are reproduced after the heading Definition below.

Action and use Antidiarrhoeal.

PreparationLoperamide Capsules

Ph Eur ___________________________________________________________________________________________________________

DEFINITION

Loperamide hydrochloride contains not less than 99.0 per cent and not more than the equivalent of101.0 per cent of 4-[4-(4-chlorophenyl)-4-hydroxypiperidino]-N,N-dimethyl-2,2-diphenyl-butyramide hydrochloride, calculated with reference to the dried substance.

CHARACTERS

A white or almost white powder, slightly soluble in water, freely soluble in methanol, soluble inalcohol.

It melts at about 225C, with decomposition.

IDENTIFICATION

First identification: A, C.Second identification: B, C.

A. Examine by infrared absorption spectrophotometry (2.2.24), comparing with the spectrumobtained with loperamide hydrochloride CRS. Examine the substances prepared as discs.

B. Examine by thin-layer chromatography (2.2.27), using as the coating substance a suitable octa-decylsilyl silica gel.

Test solution. Dissolve 30 mg of the substance to be examined in the mobile phase and dilute to 5 mlwith the mobile phase.

Reference solution (a). Dissolve 30 mg of loperamide hydrochloride CRS in the mobile phase and diluteto 5 ml with the mobile phase.

Reference solution (b). Dissolve 30 mg of loperamide hydrochloride CRS and 30 mg of ketoconazole CRSin the mobile phase and dilute to 5 ml with the mobile phase.

Apply separately to the plate 5 l of each solution. Develop over a path of 12 cm using a mixture of20 volumes of ammonium acetate solution R, 40 volumes of dioxan R and 40 volumes of methanol R.Dry the plate in a current of air for 15 min and expose it to iodine vapour until the spots appear.Examine in daylight. The principal spot in the chromatogram obtained with the test solution issimilar in position, colour and size to the principal spot in the chromatogram obtained with referencesolution (a). The test is not valid unless the chromatogram obtained with reference solution (b)shows two clearly separated spots.

C. Dissolve 50 mg in a mixture of 0.4 ml of ammonia R and 2 ml of water R. Mix, allow to stand for5 min and filter. Acidify the filtrate with dilute nitric acid R. It gives reaction (a) of chlorides (2.3.1).

TESTS

Appearance of solution Dissolve 1.0 g in methanol R and dilute to 10 ml with the same solvent.The solution is clear (2.2.1) and not more intensely coloured than reference solution BY7 (Method II,2.2.2).

Related substances Examine by liquid chromatography (2.2.29).

Test solution. Dissolve 0.10 g of the substance to be examined in methanol R and dilute to 10.0 mlwith the same solvent.

Reference solution (a). Dissolve 2.5 mg of loperamide hydrochloride CRS and 2.5 mg of haloperidol CRSin methanol R and dilute to 100.0 ml with the same solvent.

24-17

Reference solution (b). Dilute 1.0 ml of the test solution to 100.0 ml with methanol R. Dilute 5.0 ml ofthis solution to 20.0 ml with methanol R.

The chromatographic procedure may be carried out using: a stainless steel column 0.10 m long and 4.6 mm in internal diameter packed with octadecylsilyl

silica gel for chromatography R (3 m), as mobile phase at a flow rate of 2 ml per minute a mixture of 1 volume of acetonitrile R and 9

volumes of a 17 g/l solution of tetrabutylammonium hydrogen sulphate R, changing by lineargradient elution over 10 min to a mixture of 7 volumes of acetonitrile R and 3 volumes of a 17 g/lsolution of tetrabutylammonium hydrogen sulphate R; elute for a further 5 min with the final eluentmixture,

as detector a spectrophotometer set at 220 nm.Equilibrate the column for at least 30 min with acetonitrile R and then equilibrate at the initial

eluent composition for at least 5 min.Adjust the sensitivity of the detector so that the height of the principal peak in the chromatogram

obtained with reference solution (b) is 70 per cent to 90 per cent of the full scale of the recorder.Inject 10 l of reference solution (a). When the chromatogram is recorded in the prescribed condi-

tions, the retention times are: haloperidol about 3 min; loperamide hydrochloride about 4.5 min. Thetest is not valid unless the resolution between the peaks corresponding to haloperidol and loperamidehydrochloride is at least 8.0. If necessary, adjust the final concentration of acetonitrile in the mobilephase or adjust the conditions of the linear gradient.

Inject separately 10 l of methanol R as a blank, 10 l of the test solution and 10 l of referencesolution (b). In the chromatogram obtained with the test solution: the area of any peak, apart fromthe principal peak, is not greater than the area of the principal peak in the chromatogram obtainedwith reference solution (b) (0.25 per cent); the sum of the areas of all the peaks, apart from theprincipal peak, is not greater than twice the area of the principal peak in the chromatogram obtainedwith reference solution (b) (0.5 per cent). Disregard any peak obtained with methanol and any peakwith an area less than 0.2 times the area of the principal peak in the chromatogram obtained withreference solution (b).

Loss on drying (2.2.32). Not more than 0.5 per cent, determined on 1.000 g by drying in an oven at100C to 105C.


ASSAY

Dissolve 0.400 g in 50 ml of alcohol R and add 5.0 ml of 0.01M hydrochloric acid. Carry out a poten-tiometric titration (2.2.20), using 0.1M sodium hydroxide. Read the volume added between the twopoints of inflexion.

1 ml of 0.1M sodium hydroxide is equivalent to 51.35 mg of C29H34Cl2N2O2.

STORAGE


IMPURITIES

N CONMe2

PhPh

OH

Cl

A. 4-[4-(4-chlorobiphenyl-4-yl)-4-hydroxypiperidino]-N,N-dimethyl-2,2-diphenyl-butyramide,

N CONMe2

PhPh

OHCl

2

Br+

B. 4-(4-chlorophenyl)-1,1-bis[4-(dimethylamino)-4-oxo-3,3-diphenylbutyl]-4-hydroxypiperidinium bromide,

24-18

NH

OHCl

C. 4-(4-chlorophenyl)piperidin-4-ol,

N CONMe2

PhPh

OH

D.4-(4-hydroxy-4-phenylpiperidino)-N,N-dimethyl-2,2-diphenylbutyramide,

N

PhPh

OHN

O

Cl

OHCl

E. 4-(4-chlorophenyl)-1-[4-[4-(4-chlorophenyl)-4-hydroxy-piperidino]-2,2-diphenylbutyryl]piperidin-4-ol.

__________________________________________________________________________________________________________ Ph Eur

24-19

Loprazolam Mesilate

,CH3SO3H

N

N

O

N

H

NMe

Cl

O2N

C23H21ClN6O3,CH4O3S,H2O 579.1 70111-54-5

Definition Loprazolam Mesilate is (Z)-6-(2-chlorophenyl)-2,4-dihydro-2-(4-methylpiperazin-1-ylmethylene)-8-nitroimidazo[1,2-a][1,4]benzodiazepin-1-one methanesulphonate monohydrate. Itcontains not less than 98.5% and not more than 101.0% of C23H21ClN6O3,CH4O3S, calculatedwith reference to the dried substance.

Characteristics A yellow, crystalline powder.Slightly soluble in water, in chloroform and in ethanol (96%); very slightly soluble in ether.

IdentificationA. The infrared absorption spectrum, Appendix II A, is concordant with the reference spectrum ofloprazolam mesilate (RS 205).

B. The light absorption, Appendix II B, in the range 210 to 370 nm of a 0.001% w/v solution inethanol (96%) exhibits a maximum at 330 nm and a shoulder at 240 nm. The absorbance at themaximum is about 0.7.

N-Methylpiperazine Carry out the method for thin-layer chromatography, Appendix III A, using asilica gel precoated plate (Merck silica gel 60 plates are suitable) and a mixture of 80 volumes ofchloroform, 20 volumes of methanol and 2 volumes of 13.5M ammonia as the mobile phase. Applyseparately to the plate 10 l of each of two solutions in a mixture of equal volumes of chloroform andmethanol containing (1) 2.0% w/v of the substance being examined and (2) 0.0050% w/v ofN-methylpiperazine. After removal of the plate, allow it to dry in air, heat at 110 for 15 minutes andspray with a mixture of 50 volumes of a 2% w/v solution of potassium iodide and 1 volume of a 10%w/v solution of chloroplatinic(IV) acid. Any spot corresponding to N-methylpiperazine in the chrom-atogram obtained with solution (1) is not more intense than the spot in the chromatogram obtainedwith solution (2).

Related substances Carry out the method for thin-layer chromatography, Appendix III A, using asilica gel precoated plate (Merck silica gel 60 plates are suitable) and a mixture of 80 volumes ofchloroform and 20 volumes of methanol as the mobile phase. Before use, stand the plate in methanol,allowing the solvent front to ascend 17 cm, allow to dry in air, heat the plate at 100 to 105 for 1hour and use with the flow of mobile phase in the same direction as that used for the pretreatment.Apply separately to the plate 10 l of each of three solutions in a mixture of 46 volumes of chloroform,46 volumes of methanol and 8 volumes of water containing (1) 2.0% w/v of the substance beingexamined, (2) 0.0020% w/v of the substance being examined and (3) 0.010% w/v of 6-(2-chlorophenyl)-2,4-dihydro-2-[(dimethylamino)methylene]-8-nitroimidazo[1,2-a][1,4]benzodiazepin-1-oneBPCRS (dimethylamino analogue). After removal of the plate, allow it to dry in air, spray the platewith a 5% w/v solution of titanium(III) chloride in a solution of hydrochloric acid containing 10% w/vof HCl and then spray with a solution containing 0.4 g of 4-dimethylaminocinnamaldehyde in a mixtureof 20 ml of 6M hydrochloric acid and 100 ml of ethanol (96%). Heat at 100 until spots appear (about10 minutes). Any spot corresponding to the dimethylamino analogue in the chromatogram obtainedwith solution (1) is not more intense than the spot in the chromatogram obtained with solution (3)and any other secondary spot is not more intense than the spot in the chromatogram obtained withsolution (2).

Loss on drying When dried at 100 to 105 for 3 hours, loses 2.5 to 4.5% of its weight. Use 1 g.

Sulphated ash Not more than 0.1%, Appendix IX A.

Assay Dissolve 0.25 g in 60 ml of a 50% v/v solution of propan-2-ol and titrate with 0.05M sodiumhydroxide VS determining the end point potentiometrically. Each ml of 0.05M sodium hydroxide VS isequivalent to 28.05 mg of C23H21ClN6O3,CH4O3S.

Storage Loprazolam Mesilate should be kept in a well-closed container.

Action and use Hypnotic.

24-20

PreparationLoprazolam Tablets

When loprazolam mesylate is prescribed or demanded, Loprazolam Mesilate shall be dispensed orsupplied.

IMPURITIES

N

N

ONMe2

H

Cl

O2N

A. 6-(2-chlorophenyl)-2,4-dihydro-2-[(dimethylamino)methylene]-8-nitro-imidazo[1,2-a][1,4]benzodiazepin-1-one,

HNNMe

B. N-methylpiperazine.

24-21

Lorazepam

N

NCl

OH

Cl

OHH

and enantiomer

C15H10Cl2N2O2 321.2 846-49-1

Lorazepam complies with the requirements of the 3rd edition of the European Pharmacopoeia [1121]. Theserequirements are reproduced after the heading Definition below.

Action and use Anxiolytic.

PreparationsLorazepam InjectionLorazepam Tablets

Ph Eur ___________________________________________________________________________________________________________

DEFINITION

Lorazepam contains not less than 98.5 per cent and not more than the equivalent of 102.0 per centof (RS)-7-chloro-5-(2-chlorophenyl)-3-hydroxy-1,3-dihydro-2H-1,4-benzodiazepin-2-one, calculatedwith reference to the dried substance.

CHARACTERS

A white or almost white, crystalline powder, practically insoluble in water, sparingly soluble inalcohol, sparingly soluble or slightly soluble in methylene chloride.

It shows polymorphism.

IDENTIFICATION

First identification: B.Second identification: A, C.

A. Dissolve 10.0 mg in alcohol R and dilute to 100.0 ml with the same solvent. Dilute 10.0 ml of thissolution to 100.0 ml with alcohol R. Examined between 210 nm and 280 nm (2.2.25), the solutionshows an absorption maximum at 230 nm. The specific absorbance at the maximum is 1070 to1170.

B. Examine by infrared absorption spectrophotometry between 600 cm-1 and 2000 cm-1 (2.2.24),comparing with the spectrum obtained with lorazepam CRS. Examine the substances as discsprepared using potassium bromide R.

C. Examine the chromatograms obtained in the test for related substances. The principal spot in thechromatogram obtained with test solution (b) is similar in position and size to the spot in the chrom-atogram obtained with reference solution (a). The test is not valid unless the chromatogram obtainedwith reference solution (d) shows two clearly separated spots.

TESTS

Related substances Examine by thin-layer chromatography (2.2.27), using a TLC silica gel F254plate R. Place the plate in a chromatographic tank containing methanol R and allow the solvent frontto migrate over a path of 17 cm. Allow the plate to dry in air and heat it at 100C to 105C for 1 h.Test solution (a). Dissolve 0.200 g of the substance to be examined in acetone R and dilute to 10 mlwith the same solvent.Test solution (b). Dilute 2 ml of test solution (a) to 50 ml with acetone R.

Reference solution (a). Dissolve 20 mg of lorazepam CRS in acetone R and dilute to 25 ml with thesame solvent.

Reference solution (b). Dilute 1 ml of test solution (b) to 20 ml with acetone R.

Reference solution (c). Dilute 5 ml of reference solution (b) to 10 ml with acetone R.

Reference solution (d). Dissolve 4 mg of nitrazepam CRS in acetone R, add 5 ml of reference solution(a) and dilute to 20 ml with acetone R.

24-22

Apply to the plate 20 l of each solution and develop in the direction used for the migration ofmethanol over a path of 12 cm with a mixture of 10 volumes of methanol R and 100 volumes ofmethylene chloride R. Allow the plate to dry in air and examine in ultraviolet light at 254 nm. Any spotin the chromatogram obtained with test solution (a), apart from the principal spot, is not moreintense than the spot in the chromatogram obtained with reference solution (b) (0.2 per cent) and atmost one such spot is more intense than the spot in the chromatogram obtained with referencesolution (c) (0.1 per cent).

Loss on drying (2.2.32). Not more than 0.5 per cent, determined on 1.000 g under high vacuum at100C to 105C.


ASSAY

Dissolve 0.250 g in 30 ml of dimethylformamide R. Titrate with 0.1M tetrabutylammonium hydroxide,determining the end-point potentiometrically (2.2.20). Protect the solution from atmospheric carbondioxide throughout the titration.

1 ml of 0.1M tetrabutylammonium hydroxide is equivalent to 32.12 mg of C15H10Cl2N2O2.

STORAGE

Store in an airtight container, protected from light.

IMPURITIES

O

NH2

ClCl

A. 2-amino-2,5-dichlorobenzophenone,

N

NClCl

OOAcH

H

and enantiomer

B. (RS)-3-(acetyloxy)-7-chloro-5-(2-chlorophenyl)-1,3-dihydro-2H-1,4-benzodiazepin-2-one.

__________________________________________________________________________________________________________ Ph Eur

24-23

Lormetazepam

N

NCl

OMe

OH

H

Cl

and enantiomer

C16H12Cl2N2O2 335.2 848-75-9

Definition Lormetazepam is (RS)-7-chloro-5-(2-chlorophenyl)-1,3-dihydro-3-hydroxy-1-methyl-1,4-benzodiazepin-2-one. It contains not less than 99.0% and not more than 101.0% ofC16H12Cl2N2O2, calculated with reference to the dried substance.

Characteristics A white, crystalline powder.Practically insoluble in water; soluble in ethanol (96%) and in methanol.

Identification A. The infrared absorption spectrum, Appendix II A, is concordant with the referencespectrum of lormetazepam (RS 207).B. In the test for Related substances, the chromatogram obtained with solution (2) shows a peak withthe same retention time as the principal peak in the chromatogram obtained with solution (4).

Related substances Carry out the method for liquid chromatography, Appendix III D, using fivesolutions in methanol containing (1) 1.0% w/v of the substance being examined, (2) 0.0020% w/v ofthe substance being examined, (3) 0.0010% w/v of the substance being examined, (4) 0.0020% w/vof lormetazepam BPCRS, (5) 0.0010% w/v each of lormetazepam BPCRS and lorazepam BPCRS.

The chromatographic procedure may be carried out using (a) a column (20 cm 4.6 mm) packedwith stationary phase C (5 m) (Hypersil ODS is suitable), (b) as the mobile phase with a flow rate of2 ml per minute a mixture of 48 volumes of methanol and 52 volumes of a phosphate buffer preparedby dissolving 4.91 g of sodium dihydrogen orthophosphate and 0.633 g of disodium hydrogen orthophos-phate in sufficient water to produce 1000 ml and (c) a detection wavelength of 230 nm.

The test is not valid unless the resolution factor between the two principal peaks in the chromato-gram obtained with solution (5) is at least 4.

In the chromatogram obtained with solution (1) the area of any secondary peak is not greater thanthat of the principal peak in the chromatogram obtained with solution (2) (0.2%) and not more thantwo such peaks have an area greater than the area of the principal peak in the chromatogram obtainedwith solution (3) (0.1%). The sum of the areas of all such peaks is not greater than 2.5 times the areaof the principal peak obtained with solution (2) (0.5%).

Loss on drying When dried to constant weight at 105 for 3 hours, loses not more 1.0% of itsweight. Use 1 g.

Sulphated ash Not more than 0.1%, Appendix IX A.

Assay Dissolve 0.5 g in 50 ml of nitroethane and carry out Method I for non-aqueous titration,Appendix VIII A, determining the end point potentiometrically. Each ml of 0.1M perchloric acid VS isequivalent to 33.52 mg of C16H12Cl2N2O2.

Storage Lormetazepam should be kept in a well-closed container and protected from light.

Action and use Hypnotic; anxiolytic.

PreparationLormetazepam Tablets

IMPURITIES

OClCl

NHMe

A. 2-methylamino-2,5-dichlorobenzophenone

24-24

OMe

Cl

HOAc

Cl N

N

B. O3-acetyl-lormetazepam

O

ClCl NH

N OMe

C. 7-chloro-1-methyl-5-(2-chlorophenyl)-4,5-dihydro-2H-1,4-benzodiazepin-2,3-(1H)-dione

24-25

Lovage Root

Lovage Root complies with the requirements of the 3rd edition of the European Pharmacopoeia [1233]. Theserequirements are reproduced after the heading Definition below.

Ph Eur ___________________________________________________________________________________________________________

DEFINITION

Lovage root consists of the whole or cut, dried rhizome and root of Levisticum officinale Koch. Thewhole drug contains not less than 4.0 ml/kg of essential oil and the cut drug not less than 3.0 ml/kg ofessential oil, calculated with reference to the anhydrous drug.

CHARACTERS

It has the macroscopic and microscopic characters described under Identification tests A and B.

IDENTIFICATION

A. The rhizome and the large roots are often split longitudinally. The rhizome is short, up to 5 cm indiameter, light greyish-brown or yellowish-brown, simple or with several protuberances; the roots,showing little ramification, are the same colour as the rhizome; they are usually up to 1.5 cm thickand up to about 25 cm long; the fracture is usually smooth and shows a very wide yellowish-whitebark and a narrow brownish-yellow wood.

B. Reduce to a powder (355). The powder is brownish-yellow. Examine under a microscope usingchloral hydrate solution R. The powder shows: cork cells polygonal or rounded in surface view browncontents; abundant parenchyma, mostly thin-walled and rounded but some with thicker walls; groupsof small, reticulately thickened vessels embedded in small-celled, unlignified parenchyma; fragmentsof larger vessels with reticulate thickening, up to 125 m in diameter; fragments of secretory canalsup to 180 m wide. Examine under a microscope using a 50 per cent V/V solution of glycerol R. Thepowder shows starch granules, simple, rounded to ovoid, up to about 12 m, and numerous larger,compound granules, many with several components.

C. Examine the chromatogram obtained with the reference solution in the test for angelicae radix inultraviolet light at 254 nm and locate the quenching zone (eugenol). Examine in ultraviolet light at365 nm. The chromatogram obtained with the test solution shows a principal zone with intense paleblue to greenish-blue fluorescence. This zone is slightly below that of eugenol in the chromatogramobtained with the reference solution. There are one or two smaller zones with the same fluorescenceimmediately below the principal zone. Other zones with less intense fluorescence are visible in thelower part of the chromatogram obtained with the test solution.

TESTS

Angelicae radix Examine by thin-layer chromatography (2.2.27) using as the coating substance asuitable silica gel with a fluorescent indicator having an optimal intensity at 254 nm.

Test solution. Shake 2 g of the freshly powdered drug (500) with 10 ml of a mixture of equal volumesof methanol R and of methylene chloride R for 10 min and filter.

Reference solution. Dissolve 50 mg of eugenol R in a mixture of equal volumes of methanol R and ofmethylene chloride R. Dilute to 10.0 ml with the same mixture of solvents.

Apply separately to the plate as bands 10 l of each solution. Develop over a path of 10 cm using amixture of equal volumes of methylene chloride R and of toluene R. Allow the plate to dry in air anddevelop again over a path of 10 cm using the same mobile phase. Allow the plate to dry in air andexamine in ultraviolet light at 365 nm. The chromatogram obtained with the test solution shows nointense blue or bluish-violet fluorescent zone in the lower third.

Foreign matter (2.8.2). Not more than 3 per cent, determined on 50 g.

Total ash (2.4.16). Not more than 8.0 per cent.

Ash insoluble in hydrochloric acid (2.8.1). Not more than 2.0 per cent.

Water (2.2.13). Not more than 12.0 per cent, determined on 25.00 g by distillation.

ASSAY

Carry out the determination of essential oils in vegetable drugs (2.8.12). Use a 2 litre flask, ten dropsof liquid paraffin R, 500 ml of water R as the distillation liquid and 0.50 ml of xylene R in thegraduated tube. Reduce the drug to a powder (500) and immediately use 40.0 g for the determina-tion. Distil at a rate of 2 ml/min to 3 ml/min for 4 h.

STORAGE

Store in a well-closed container, protected from light.__________________________________________________________________________________________________________ Ph Eur

24-26

Lovastatin

1/01

OH3C

O

MeH

O

HO O

H

HMe

Me

H

H

H

H

C24H36O5 404.5 75330-75-5

Lovastatin complies with the requirements of the 3rd edition of the European Pharmacopoeia [1538]. Theserequirements are reproduced after the heading Definition below.

Action and use Hypolipidaemic.

Ph Eur ___________________________________________________________________________________________________________

DEFINITION

Lovastatin contains not less than 97.0 per cent and not more than the equivalent of 102.0 per cent of(1S,3R,7S,8S,8aR)-8-[2-[(2R,4R)-4-hydroxy-6-oxotetrahydro-2H-pyran-2-yl]ethyl]-3,7-dimethyl-1,2,3,7,8,8a-hexahydronaphthalen-1-yl (2S)-2-methylbutanoate, calculated with reference to thedried substance.

PRODUCTION

Where applicable, it complies with the requirements of the monograph on Products of fermentation(1468).

CHARACTERS

A white or almost white crystalline powder, practically insoluble in water, soluble in acetone, spar-ingly soluble in ethanol.

IDENTIFICATION

A. It complies with the test for specific optical rotation (see Tests).

B. Examine by infrared absorption spectrophotometry (2.2.24), comparing with the spectrumobtained with lovastatin CRS. Examine the substances prepared as discs.

TESTS

Appearance of solution Dissolve 0.200 g in acetonitrile R and dilute to 20.0 ml with the samesolvent. The solution is clear (2.2.1) and not more intensely coloured than reference solution B6 orBY6 (Method II, 2.2.2).

Specific optical rotation (2.2.7). Dissolve 0.125 g in acetonitrile R and dilute to 25.0 ml with thesame solvent. The specific optical rotation is +325 to +340, calculated with reference to the driedsubstance.

Related substances Examine by liquid chromatography (2.2.29) as described under Assay.Inject 10 l of reference solution (b). Adjust the sensitivity of the system so that the height of the

principal peak is at least 20 per cent of the full scale of the recorder. Inject 10 l of test solution (a).When the chromatograms are recorded under the prescribed conditions the relative retentions are:impurity A about 0.8, impurity B about 0.6, impurity C about 1.2 and impurity D about 2.3 (reten-tion time of lovastatin: about 7 min). In the chromatogram obtained with test solution (a): the area ofany peak, apart from the principal peak, is not greater than 0.6 times the area of the principal peak inthe chromatogram obtained with reference solution (b) (0.3 per cent); the sum of the areas of allpeaks, apart from the principal peak, is not greater than twice the area of the principal peak in thechromatogram obtained with reference solution (b) (1 per cent). Disregard any peak with an area lessthan 0.1 times the area of the principal peak in the chromatogram obtained with reference solution(b) (0.05 per cent).

Heavy metals (2.4.8).1.0 g complies with limit test C for heavy metals (20 ppm). Prepare thestandard using 2 ml of lead standard solution (10 ppm Pb) R.

24-27

Loss on drying (2.2.32). Not more than 0.5 per cent, determined on 1.000 g by drying in adesiccator under high vacuum at 60C for 3 h.


ASSAY

Examine by liquid chromatography (2.2.29).

Test solution (a). Dissolve 20.0 mg of the substance to be examined in acetonitrile R and dilute to50.0 ml with the same solvent.

Test solution (b). Dilute 10.0 ml of test solution (a) to 20.0 ml with acetonitrile R.

Reference solution (a). Dissolve 10.0 mg of lovastatin CRS in acetonitrile R and dilute to 50.0 ml withthe same solvent.

Reference solution (b). Dilute 0.5 ml of test solution (a) to 100.0 ml with acetonitrile R.

Reference solution (c). To 5.0 ml of reference solution (a) add 1 mg of simvastatin CRS and dilute to50.0 ml with acetonitrile R.

The chromatographic procedure may be carried out using: a stainless steel column 0.25 m long and 4.6 mm in internal diameter packed with octylsilyl silica

gel for chromatography R (5 m), as mobile phase at a flow rate of 1.5 ml/min:

Mobile phase A. Acetonitrile R,

Mobile phase B. A 0.1 per cent V/V solution of phosphoric acid R,

Time(min)

Mobile phase A(per cent V/V)

Mobile phase B(per cent V/V)

Comment

05 60 40 Isocratic

57 60 65 40 35 Linear gradient


1315 90 10 Isocratic


1720 60 40 Re-equilibration

as detector a spectrophotometer set at 238 nm.Inject 10 l of reference solution (c). The test is not valid unless, in the chromatogram obtained,

the resolution between the peaks corresponding to simvastatin and lovastatin is at least 5.0. When thechromatograms are recorded in the prescribed conditions the relative retention of simvastatin is about1.1 (retention time of lovastatin: about 7 min). Inject 10 l of reference solution (a). Adjust thesensitivity of the system so that the height of the principal peak is at least 50 per cent of the full scaleof the recorder. Inject 10 l of test solution (b).

Calculate the content of C24H36O5 from the peak areas in the chromatograms obtained with testsolution (b) and reference solution (a), and the declared content of C24H36O5 in lovastatin CRS.

STORAGE

Store under nitrogen at a temperature of 2C to 8C.

IMPURITIES

OH3C

O

MeHH

Me

Me

H

H

HR =

O3C

O

MeH

O

HO O

H

HMe

H

H

H

H

A. (1S,7S,8S,8aR)-8-[2-[(2R,4R)-4-hydroxy-6-oxotetrahydro-2H-pyran-2-yl]ethyl]-7-methyl-1,2,3,7,8,8a-hexahydronaphthalen-1-yl (2S)-2-methylbutanoate (mevastatin),

24-28

OH

OH

R H

COOH

B. (3R,5R)-7-[(1S,2S,6R,8S,8aR)-2,6-dimethyl-8-[[(2S)-2-methylbutanoyl]oxy]-1,2,6,7,8,8a-hexahydronaphthalen-1-yl]-3,5-dihydroxyheptanoic acid (hydroxyacidlovastatin),

O

O

HRC. (1S,3R,7S,8S,8aR)-3,7-dimethyl-8-[2-[(2R)-6-oxo-3,6-dihydro-2H-pyran-2-yl]ethyl]-

1,2,3,7,8,8a-hexahydronaphthalen-1-yl (2S)-2-methylbutanoate (dehydrolovastatin),

O

O

HR

OH

OH

R H

O

O

D. (2R,4R)-2-[2-[(1S,2S,6R,8S,8aR)-2,6-dimethyl-8-[[(2S)-2-methylbutanoyl]oxy]-1,2,6,7,8,8a-hexahydronaphthalen-1-yl]ethyl]-6-oxotetrahydro-2H-pyran-4-yl (3R,5R)-7-[(1S,2S,6R,8S,8aR)-2,6-dimethyl-8-[[(2S)-2-methylbutanoyl]oxy]-1,2,6,7,8,8a-hexahydronaphthalen-1-yl]-3,5-dihydroxyheptanoate (lovastatin dimer).

__________________________________________________________________________________________________________ Ph Eur

24-29

Lymecycline992-21-2

Definition Lymecycline is a water-soluble combination of tetracycline, lysine and formaldehyde.The potency is not less than 900 IU per mg, calculated with reference to the anhydrous substance.

Characteristics A yellow powder; very hygroscopic.Very soluble in water; slightly soluble in ethanol (96%); practically insoluble in acetone, in chloroform

and in ether.

IdentificationA. Carry out the method for thin-layer chromatography, Appendix III A, using silica gel H as the coat-ing substance and a mixture of 6 volumes of water, 35 volumes of methanol and 59 volumes ofdichloromethane as the mobile phase. Adjust the pH of a 10% w/v solution of disodium edetate to 8.0with 10M sodium hydroxide and spray the solution evenly onto the plate (about 10 ml for a plate100 mm 200 mm). Allow the plate to dry in a horizontal position for at least 1 hour. Before use,dry the plate in an oven at 110 for 1 hour. Apply separately to the plate 1 l of each of three solu-tions in methanol containing (1) 0.05% w/v of the substance being examined, (2) 0.05% w/v oflymecycline BPCRS and (3) 0.05% w/v each of tetracycline hydrochloride EPCRS, chlortetracyclinehydrochloride EPCRS and doxycycline hyclate EPCRS. After removal of the plate, allow it to dry in acurrent of air and examine under ultraviolet light (365 nm). The principal spot in the chromatogramobtained with solution (1) is similar in position, colour and size to that in the chromatogram obtainedwith solution (2). The test is not valid unless the chromatogram obtained with solution (3) showsthree clearly separated spots.

B. To 0.5 mg add 2 ml of sulphuric acid. A purplish red colour is produced.

C. Dissolve 50 mg in 5 ml of water, add 50 mg of ninhydrin, boil and add 15 ml of water. A bluishviolet colour is produced.

D. Dissolve 0.2 g in 5 ml of water, add 0.3 ml of orthophosphoric acid and distil. To 1 ml of thedistillate add 10 ml of chromotropicsulphuric acid solution. A violet colour is produced.

Alkalinity pH of a 1% w/v solution, 7.8 to 8.1, Appendix V L.

Light absorption To 10 ml of a 0.01% w/v solution in 0.01M hydrochloric acid add 75 ml of waterand 5 ml of 5M sodium hydroxide, add sufficient water to produce 100 ml and mix immediately. Theabsorbance of the resulting solution at the maximum at 380 nm, when measured exactly 6 minutesafter the addition of the sodium hydroxide solution, is 0.27 to 0.31, calculated with reference to theanhydrous substance, Appendix II B.

Specific optical rotation In a 0.5% w/v solution, 180 to 210, calculated with reference to theanhydrous substance, Appendix V F.

Light-absorbing impurities The absorbance of a 0.25% w/v solution in 0.01M hydrochloric acid at430 nm, when measured within 1 hour of preparing the solution, is not more than 0.50, calculatedwith reference to the anhydrous substance, Appendix II B.

Free tetracycline To 0.5 g add 50 ml of butyl acetate and allow to stand for 1 hour at 25. Filter andextract the filtrate with two 25-ml quantities of 0.1M hydrochloric acid. Combine the extracts, addsufficient 0.1M hydrochloric acid to produce 50 ml and dilute 10 ml of this solution to 100 ml with0.1M hydrochloric acid. The absorbance of the resulting solution at 355 nm is not more than 0.64,calculated with reference to the anhydrous substance, Appendix II B.

Related substances Carry out the method for thin-layer chromatography, Appendix III A, using aplate prepared in the following manner. Boil 50 g of keiselguhr G with a mixture of 250 ml ofhydrochloric acid and 250 ml of water for 10 minutes, filter and wash the filter with water until thewashings are alkaline to congo red solution. Dry the residue at 105 and slurry 25 g with a mixture of2.5 ml of a 20% v/v solution of polyethylene glycol 400 in glycerol and 47.5 ml of 0.1M disodium edetatepreviously adjusted to pH 7 with 5M ammonia. After spreading the plate, allow it to dry at roomtemperature until the surface acquires a uniform matt appearance (usually after 1 to 2 hours) andplace in a tank the atmosphere of which has been allowed to equilibrate with a saturated solution ofammonium chloride for at least 24 hours. Allow the plate to remain in the tank for 24 hours and useimmediately after removal. Use as the mobile phase the solution obtained by shaking 5 ml of 0.1Mdisodium edetate, previously adjusted to pH 7 with 5M ammonia, with 200 ml of a mixture consistingof 3 volumes of acetone, 1 volume of chloroform and 1 volume of ethyl acetate, the emulsion beingremoved by filtering through absorbent cotton. Apply separately to the plate 1 l of each of thefollowing solutions. For solution (1) add 5 ml of water and 1 ml of a 4% w/v solution of sodiummetabisulphite to 0.125 g of the substance being examined and allow to stand for 16 hours at roomtemperature, without stirring. Add sufficient 0.1M hydrochloric acid to produce 10 ml and filter ifnecessary. Solutions (2) to (5) are freshly prepared solutions in methanol containing (2) 0.0050% w/vof anhydrotetracycline hydrochloride EPCRS, (3) 0.0050% w/v of 4-epianhydrotetracycline hydrochloride

24-30

EPCRS, (4) 0.020% w/v of chlortetracycline hydrochloride EPCRS and (5) 0.050% w/v of 4-epitetra-cycline hydrochloride EPCRS. After removal of the plate, allow it to dry in air, expose to the vapour of13.5M ammonia and examine under ultraviolet light (365 nm). Any secondary spot in the chromatogramobtained with solution (1) is not more intense than the corresponding spot in the chromatogramsobtained with solutions (2) to (5).

Water Not more than 5.0% w/w, Appendix IX C. Use 0.5 g.

Assay Carry out the biological assay of antibiotics, Appendix XIV A. The precision of the assay is suchthat the fiducial limits of error are not less than 95% and not more than 105% of the estimatedpotency.

Storage Lymecycline should be kept in a well-closed container, protected from light and stored at atemperature not exceeding 25.

Labelling The label states (1) the number of IU (Units), per mg; (2) the date after which thematerial is not intended to be used; (3) the conditions under which it should be stored.

Action and use Antibacterial.

PreparationLymecycline Capsules

135 mg of Lymecycline is equivalent to approximately 100 mg of tetracycline.

24-31

Lynestrenol

HH

H H

Me OH

C CH

C20H28O 284.4 52-76-6

Lynestrenol complies with the requirements of the 3rd edition of the European Pharmacopoeia [0558]. Theserequirements are reproduced after the heading Definition below.

Action and use Progestogen.

When lynoestrenol is prescribed or demanded, Lynestrenol shall be dispensed or supplied.

Ph Eur ___________________________________________________________________________________________________________

DEFINITION

Lynestrenol contains not less than 98.0 per cent and not more than the equivalent of 102.0 per centof 19-nor-17-pregn-4-en-20-yn-17-ol, calculated with reference to the dried substance.

CHARACTERS

A white or almost white, crystalline powder, practically insoluble in water, soluble in acetone, inalcohol and in ether.

IDENTIFICATION

First identification: B.Second identification: A, C.

A. Melting point (2.2.14): 161C to 165C.

B. Examine by infrared absorption spectrophotometry (2.2.24), comparing with the spectrumobtained with lynestrenol CRS.

C. Examine the chromatograms obtained in the test for related substances in ultraviolet light at365 nm. The principal spot in the chromatogram obtained with test solution (b) is similar in position,fluorescence and size to the principal spot in the chromatogram obtained with reference solution (b).

TESTS

Appearance of solution Dissolve 0.2 g in alcohol R and dilute to 10 ml with the same solvent. Thesolution is clear (2.2.1) and colourless (Method II, 2.2.2).

Specific optical rotation (2.2.7). Dissolve 0.900 g in alcohol R and dilute to 25.0 ml with the samesolvent. The specific optical rotation is 9.5 to 11, calculated with reference to the driedsubstance.

Related substances Examine by thin-layer chromatography (2.2.27), using silica gel G R as thecoating substance.

Test solution (a). Dissolve 0.125 g of the substance to be examined in chloroform R and dilute to 25 mlwith the same solvent.

Test solution (b). Dilute 5 ml of test solution (a) to 10 ml with chloroform R.

Reference solution (a). Dilute 1 ml of test solution (a) to 100 ml with chloroform R. Dilute 5 ml of thesolution to 10 ml with chloroform R.

Reference solution (b). Dissolve 25 mg of lynestrenol CRS in chloroform R and dilute to 10 ml with thesame solvent.

Apply separately to the plate 10 l of each solution. Develop over a path of 15 cm using a mixture of20 volumes of acetone R and 80 volumes of heptane R. Allow the plate to dry in air, spray with 0.25Malcoholic sulphuric acid and heat at 105C for 10 min. Examine in ultraviolet light at 365 nm. Any spotin the chromatogram obtained with test solution (a), apart from the principal spot, is not moreintense than the spot in the chromatogram obtained with reference solution (a) (0.5 per cent).


24-32

ASSAY

Dissolve 0.150 g in 40 ml of tetrahydrofuran R and add 5.0 ml of a 100 g/l solution of silver nitrate R.Titrate with 0.1M sodium hydroxide. Determine the end-point potentiometrically (2.2.20), using aglass indicator electrode and as comparison electrode a silver-silver chloride double-junction electro-de with a saturated solution of potassium nitrate R as junction liquid. Carry out a blank titration.

1 ml of 0.1M sodium hydroxide is equivalent to 28.44 mg of C20H28O.

STORAGE


24-33

Lysine Hydrochloride

H2N COOH

H NH2

,HCl

C6H14N2O2,HCl 182.7 657-27-2

Lysine Hydrochloride complies with the requirements of the 3rd edition of the European Pharmacopoeia [0930].These requirements are reproduced after the heading Definition below.

Action and use Amino acid.

Ph Eur ___________________________________________________________________________________________________________

DEFINITION

Lysine hydrochloride contains not less than 98.5 per cent and not more than the equivalent of101.0 per cent of (S)-2,6-diaminohexanoic acid hydrochloride, calculated with reference to the driedsubstance.

PRODUCTION

When Lysine hydrochloride is produced by a process involving fermentation steps, it complies withthe requirements of the monograph on Products of fermentation (1468).

CHARACTERS

A white, crystalline powder or colourless crystals, freely soluble in water, slightly soluble in alcohol,practically insoluble in ether.

IDENTIFICATION

First identification: A, B, E.Second identification: A, C, D, E.

A. It complies with the test for specific optical rotation (see Tests).

B. Examine by infrared absorption spectrophotometry (2.2.24), comparing with the spectrumobtained with lysine hydrochloride CRS. Examine the substances prepared as discs. If the spectraobtained show differences, dissolve the substance to be examined and the reference substanceseparately in the minimum volume of water R, evaporate to dryness at 60C, and record new spectrausing the residues.

C. Examine the chromatograms obtained in the test for ninhydrin-positive substances. The principalspot in the chromatogram obtained with test solution (b) is similar in position, colour and size to theprincipal spot in the chromatogram obtained with reference solution (a).

D. To 0.1 ml of solution S (see Tests) add 2 ml of water R and 1 ml of a 50 g/l solution ofphosphomolybdic acid R. A yellowish-white precipitate is formed.

E. To 0.1 ml of solution S add 2 ml of water R. The solution gives reaction (a) of chlorides (2.3.1).

TESTS

Solution S Dissolve 5.0 g in carbon dioxide-free water R prepared from distilled water R and dilute to50 ml with the same solvent.

Appearance of solution Solution S is clear (2.2.1) and not more intensely coloured than referencesolution B7 or GY7 (Method II, 2.2.2).

Specific optical rotation (2.2.7). Dissolve 2.00 g in hydrochloric acid R1 and dilute to 25.0 ml withthe same acid. The specific optical rotation is +21.0 to +22.5, calculated with reference to the driedsubstance.

Ninhydrin-positive substances Examine by thin-layer chromatography (2.2.27), using a TLC silicagel plate R.

Test solution (a). Dissolve 0.10 g of the substance to be examined in water R and dilute to 10 ml withthe same solvent.

Test solution (b). Dilute 1 ml of test solution (a) to 50 ml with water R.

Reference solution (a). Dissolve 10 mg of lysine hydrochloride CRS in water R and dilute to 50 ml withthe same solvent.

Reference solution (b). Dilute 5 ml of test solution (b) to 20 ml with water R.

Reference solution (c). Dissolve 10 mg of lysine hydrochloride CRS and 10 mg of arginine CRS in water Rand dilute to 25 ml with the same solvent.

Apply separately to the plate 5 l of each solution. Develop over a path of 15 cm using a mixture of

24-34

30 volumes of concentrated ammonia R and 70 volumes of 2-propanol R. Dry the plate at 100C to105C until the ammonia disappears completely. Spray with ninhydrin solution R and heat at 100Cto 105C for 15 min. Any spot in the chromatogram obtained with test solution (a), apart from theprincipal spot, is not more intense than the spot in the chromatogram obtained with reference solu-tion (b) (0.5 per cent). The test is not valid unless the chromatogram obtained with reference solu-tion (c) shows two clearly separated spots.

Sulphates (2.4.13). Dilute 5 ml of solution S to 15 ml with distilled water R. The solution complieswith the limit test for sulphates (300 ppm).

Ammonium Prepare a cell consisting of two watch-glasses 60 mm in diameter placed edge to edge.To the inner wall of the upper watch-glass stick a piece of red litmus paper R 5 mm square and wettedwith a few drops of water R. Finely powder the substance to be examined, place 50 mg in the lowerwatch-glass and dissolve in 0.5 ml of water R. To the solution add 0.30 g of heavy magnesium oxide R.Briefly triturate with a glass rod. Immediately close the cell by putting the two watch-glasses together.Heat at 40C for 15 min. The litmus paper is not more intensely blue coloured than a standardprepared at the same time and in the same manner using 0.1 ml of ammonium standard solution(100 ppm NH4) R, 0.5 ml of water R and 0.30 g of heavy magnesium oxide R (200 ppm).

Iron (2.4.9). In a separating funnel, dissolve 0.33 g in 10 ml of dilute hydrochloric acid R. Shake withthree quantities, each of 10 ml, of methyl isobutyl ketone R1, shaking for 3 min each time. To thecombined organic layers add 10 ml of water R and shake for 3 min. The aqueous layer complies withthe limit test for iron (30 ppm).




ASSAY

Dissolve 0.150 g in 5 ml of anhydrous formic acid R. Add 50 ml of anhydrous acetic acid R. Titrate with0.1M perchloric acid, determining the end-point potentiometrically (2.2.20).

1 ml of 0.1M perchloric acid is equivalent to 18.27 mg of C6H15ClN2O2.

STORAGE


24-35

Macrogols

revised 1/01

Macrogols comply with the requirements of the 3rd edition of the European Pharmacopoeia [1444]. Theserequirements are reproduced after the heading Definition below.

The label states the type of macrogol in terms of a nominal relative molecular mass.

Action and use Pharmaceutical aids.

Ph Eur ___________________________________________________________________________________________________________

DEFINITION

Macrogols are mixtures of polymers with the general formula H-(OCH2-CH2)n-OH, correspondingto an average relative molecular mass of the labelled nominal value (n). A suitable stabiliser may beadded.

CHARACTERS

Clear, viscous, colourless or almost colourless, hygroscopic liquids, or white or almost white solidswith a waxy or paraffin-like appearance, miscible with or very soluble in water, in alcohol and inmethylene chloride, practically insoluble in fatty oils and in mineral oils.

IDENTIFICATION

A. It complies with the test for viscosity (see Tests).

B. To 1 g in a test-tube add 0.5 ml of sulphuric acid R, close the test-tube with a stopper fitted with abent delivery tube and heat until white fumes are evolved. Collect the fumes via the delivery tube into1 ml of mercuric chloride solution R. An abundant white, crystalline precipitate is formed.

C. To 0.1 g add 0.1 g of potassium thiocyanate R and 0.1 g of cobalt nitrate R, and mix thoroughly witha glass rod. Add 5 ml of methylene chloride R and shake. The liquid phase becomes blue.

TESTS

Appearance of solution Dissolve 12.5 g in water R and dilute to 50 ml with the same solvent. Thesolution is clear (2.2.1) and not more intensely coloured than reference solution BY6 (2.2.2, MethodII).

Acidity or alkalinity Dissolve 5.0 g in 50 ml of carbon dioxide-free water R and add 0.15 ml ofbromothymol blue solution R1. The solution is yellow or green. Not more than 0.1 ml of 0.1M sodiumhydroxide is required to change the colour of the indicator to blue.

Viscosity (2.2.9). The viscosity is calculated using a density given in Table 1444.-1.

Table 14441

Type ofmacrogol

Kinematicviscosity

(mm2sec 1)

Dynamicviscosity(mPas)

Density

(g/ml)

300 71 to 94 80 to 105 1.120400 94 to 116 105 to 130 1.120600 13.9 to 18.5 15 to 20 1.080

1000 20.4 to 27.7 22 to 30 1.0801500 31 to 46 34 to 50 1.0803000 69 to 93 75 to 100 1.0803350 76 to 110 83 to 120 1.0804000 102 to 158 110 to 170 1.0806000 185 to 250 200 to 270 1.0808000 240 to 472 260 to 510 1.080

20,000 2500 to 3200 2700 to 3500 1.08035,000 10,000 to 13,000 11,000 to 14,000 1.080

For macrogols having a relative molecular mass greater than 400, determine the viscosity on a 50 percent m/m solution of the substance to be examined.

Freezing point (2.2.18). See Table 1444.-2.

24-36

Table 14442

Type of macrogol Freezing point (C)

600 15 to 251000 35 to 401500 42 to 483000 50 to 563350 53 to 574000 53 to 596000 55 to 618000 55 to 62

20,000 not less than 5735,000 not less than 57

Hydroxyl value Introduce m g (see Table 1444.-3) into a dry conical flask fitted with a refluxcondenser. Add 25.0 ml of phthalic anhydride solution R, swirl to dissolve and boil under a refluxcondenser on a hot plate for 60 min. Allow to cool. Rinse the condenser first with 25 ml of pyridine Rand then with 25 ml of water R, add 1.5 ml of phenolphthalein solution R and titrate with 1M sodiumhydroxide until a faint pink colour is obtained (n1 ml). Carry out a blank test (n2 ml). Calculate thehydroxyl value using the expression:

mnn )(1.56 12

Table 14443

Type of macrogol Hydroxyl value m (g)

300 340 to 394 1.5400 264 to 300 1.9600 178 to 197 3.5

1000 107 to 118 5.01500 70 to 80 7.03000 34 to 42 12.03350 30 to 38 12.04000 25 to 32 14.06000 16 to 22 18.08000 12 to 16 24.0

20,000 35,000

For macrogols having a relative molecular mass greater than 1000, if the water content is more than0.5 per cent, dry a sample of suitable mass at 100C to 105C for 2 h and carry out the determina-tion of the hydroxyl value on the dried sample.

Reducing substances Dissolve 1 g in 1 ml of a 10 g/l solution of resorcinol R and warm gently ifnecessary. Add 2 ml of hydrochloric acid R. After 5 min the solution is not more intensely colouredthan reference solution R3 (2.2.2, Method I).

FormaldehydeTest solution. To 1.00 g add 0.25 ml of chromotropic acid, sodium salt solution R, cool in iced water andadd 5.0 ml of sulphuric acid R. Allow to stand for 15 min and complete slowly to 10 ml with water R.

Reference solution. Dilute 0.430 g of formaldehyde solution R to 100 ml with water R. Dilute 1.0 ml ofthis solution to 100 ml with water R. In a 10 ml flask, mix 1.00 ml of this solution with 0.25 ml ofchromotropic acid, sodium salt solution R, cool in iced water and add 5.0 ml of sulphuric acid R. Allow tostand for 15 min and complete slowly to 10 ml with water R.

Blank solution. In a 10 ml flask mix 1.00 ml of water R with 0.25 ml of chromotropic acid, sodium saltsolution R, cool in iced water and add 5.0 ml of sulphuric acid R. Complete slowly to 10 ml withwater R.

Determined at 567 nm against the blank solution, the absorbance of the test solution is not highert

Documents

BP_02 - 2001