Official Solutions Grade 3

lec:3Dr. Rozhan Arif

TIUFACULTY OF PHARMACY

PHARMACEUTICS I2021- 2022

Outline

Official Solutions

• Definition

• Uses of Official solutions

• Methods of preparation and Examples

Definition

Are those solutions which their full formula can be found in pharmacopeia, this is usually indicated by the presence of the names (ex, USP, BP, NF).

The most common solvent used in preparation of solution other than water are alcohol and glycerin.

Alcohol

• Is a good solvent for many organic substances, both natural and synthetic. It dissolves important plant constituents such as resins, volatile oils, alkaloids, glycosides.

• Next in useful to water, alcohol produces solutions which, in many instances, have a greater stability than their aqueous counterparts.

• hydro alcoholic liquids are commonly used as solvents for plant constituents (because they effectively dissolve the active principles; yet they do not dissolve therapeutically inert plant materials like gums and starches.

Glycerin:

• Is miscible with both water and alcohol, it is an excellent solvent for tannins, phenol and boric acid. Because of preservative qualities it is some time used as a stabilizer of solutions prepared with other solvents.

• When used as a solvent, glycerin must be heated in order to reduce its viscosity.

Uses of Official Solution

Used for many and various purposes, such as:

1) For their medical activity either internally or externally depending on the ingredients which they contain.

2) As solvent for other liquid preparations.

3) Other serves as coloring or flavoring agents for pharmaceutical products.

4)Reagent in various processes.

Methods for preparation of official solution

Solutions prepared by simple solution.

Solutions prepared by chemical reaction method.

Solutions prepared by simple solution with sterilization (such as anticoagulant and ophthalmic solution).

Solutions prepared by extraction.

• Most pharmaceutical solutions are unsaturated with solute. Thus, the amounts of solute to be dissolved are usually well below the capacity of the volume of solvent employed

• The strengths of pharmaceutical preparations are usually expressed in terms of percent strength

• If volatile solutes are to be dissolved or if the solvent is volatile (as is alcohol), the heat would encourage the loss of these agents to the atmosphere.

Simple solution method

The procedure to prepare simple solution:

1. Weight the solid ingredients then dissolved it in ¾ of the solvent in beaker after subtract the volume of any liquid.

2. Add the liquid ingredient if present.

3. Complete the volume of Rx by addition of solvent.

4. Transfer it into specialized bottle and label it.

Examples of solution prepared by simple solution:

Amaranth solution USP 1%: prepared by dissolving amaranth in purified water. It is used as coloring agent to impart color to clear liquid preparation.

Gentian violet solution USP 1%: gentian violet in hydroalcoholic solution (10% alcohol v/v). It is used as topical local anti-infective it is used topically in undiluted form in infections caused by gram-positive bacteria or by certain parasitic fungi.

Iodine solution NF: it is used as local anti-infective for skin and surgical disinfectant.

Tolnaftate solution USP 1% in a non aqueous homogeneous vehicle of polyethylene glycol 400.

Clindamycin phosphate topical solution: used in treatment of acne vulgaris.

Official Solution

Official Solution

Chemical Reaction Method • Chemical reactions take place to prepare the solution.

• Sometime the same solution can be prepared by two methods, simple solution and chemical reaction method.

Example: Calcium hydroxide solution (known as lime water) is prepared according to simple solution by dissolving Ca(OH)2 in water and by chemical reaction by shaking lime CaO with an excess of water as shown in equation

CaO +H2O Ca (OH)2

Why we choose the chemical reaction method???

1. The active constituents are not readily obtained by other method. Ex: formaldehyde

2. Several products of chemical reaction had used for therapeutic action . Ex: magnesium citrate solution. (Used as cathartic).

3. The pure solute may not dissolve from solid state . So it is obtained by chemical reaction.

Sometimes if a solution could be prepared by simple solution and by

chemical reaction, then solution prepared by simple solution is preferred.

This is because

chemical reaction is not easy method; it involves using many reagents resulting

in many compounds hard to be purified.

It contains all the products of the reaction that have taken place during

the method of preparation

Examples of Chemical Reaction Method

Hydrogen peroxide solution USP (H2O2) is also called hydrogen dioxide.

Preparation: No official procedure is given for the preparation of this solution, since it can be prepared by several methods.

• The Hydrogen peroxide may be generated by the decomposition of barium peroxide with phosphoric acid or diluted sulfuric acid:

BaO2 + H3PO4 -------> BaHPO4 + H2O2

BaO2 + H2SO4 ------> BaSO4 + H2O2

• It is also prepared by hydrolysis of persulfuric acid, which is prepared by the electrolytic oxidation of sulfuric acid.

Hydrogen Peroxide Solution USP• Hydrogen peroxide can easily break down, or

decompose, into water and oxygen

• 3% of H2O2 is capable of liberating 10 times of its volume oxygen (its called 10 volume peroxide that means 10 cm3 of oxygen gas are produced by every 1 cm3 of hydrogen peroxide).

Official Solution

Simple Solution with Sterilization Method

This solutions need sterilization because it is used for sensitive organs.

Solution prepared by simple solution with sterilization

Anti-coagulants:

Heparin solution USP sterile solution of 75,000 units of sodium heparin in sodium chloride injection.

Irrigating solution: it is used to flush or clean wounds or surgical tissues, should be sterilized because is used for sensitive areas of the body.

Example of irrigating solution aminoacetic acid sterile solution (NF): it consists from sterile solution of 1.5 and 15% . 15% aminoacetic acid in water for injection is used for irrigating solution in operation such that of prostate (prostatectomy).

Physiologic solutions:

Ringer's solution (NF), it is a solution consists from NaCl , KCl, CaCl2 diluted in purified water.

Ringer's could be considered as irrigating and physiologic solutions, and used as solvent for compound used topically for delicate membrane, use to keep living tissues to reverse all reflexes for a period of time.

• Ringer's solution, sometimes called trichloride solution .

Official Solution

(Isotonic solution of trichloride)

Solutions Prepared by Extraction

• They are used to isolate active principles from crude drug

• Example: Epinephrine solution (adrenalin chloride USP) diluted to 1: 1000 in purified water. It is prepared with the help of hydrochloric acid; it is used as vasoconstrictor to increase blood pressure, to prevent hemorrhage and to prolong action of local anesthetic for dentistry purposes

Extraction: include

maceration &

percolation.