A REVIEW ON CAPILLARY ELECTROPHORESIS MASS …. RPA1516248015.pdf · Fig.1. Block diagram of Capillary Electrophoresis mass spectrometry Principle: CEMS work by the both the principles

96 | P a g e International Standard Serial Number (ISSN): 2319-8141

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International Journal of Universal Pharmacy and Bio Sciences 4(5): September-October 2015

INTERNATIONAL JOURNAL OF UNIVERSAL

PHARMACY AND BIO SCIENCES IMPACT FACTOR 2.093***

ICV 5.13***

Pharmaceutical Sciences REVIEW ARTICLE …………!!!

A REVIEW ON CAPILLARY ELECTROPHORESIS MASS SPECTROMETRY

Ch. Aparna* and D. Gowrisankar

University College of Pharmaceutical Sciences, Andhra University, Visakhapatnam, Andhra

Pradesh, Pin code - 530003.

KEYWORDS:

CEMS, modes of

separation interfaces

applications.

For Correspondence:

Ch. Aparna*

Address:

University College of

Pharmaceutical Sciences,

Andhra University,

Visakhapatnam, Andhra

Pradesh, Pin code -

530003.

ABSTRACT

Capillary electrophoresis (CE) has wide range of applicability for the

separation of the compounds depending on their charge and mass. It is

the choice of separation technique for large and small molecules

especially biological samples. Coupling of CE with mass spectrometry

increases the applicability of the technique by providing

characterization of the samples separated by CE. Capillary

electrophoresis mass spectrometry (CEMS) became popular analytical

technique due to efficient and selective separation in combination with

powerful detection allowing identification and detailed

characterization. Here, detailed information about interfaces used in

CEMS, modes of separations and applications are reviewed and

discussed.



INTRODUCTION:

CEMS (Capillary Electrophoresis-Mass Spectrometry) is an analytical technique combined the uses of

liquid separation process of capillary electrophoresis with mass spectrometry. CEMS provide high

separation efficiency and molecular mass information in a single analysis. Since its introduction in

1987, new developments and application has made CEMS powerful separation and identification

technique. Use of CEMS has increased for protein and peptides analysis and other biomolecules. The

original interface between capillary zone electrophoresis and mass spectrometry was developed in

1987 by Richard D. Smith and coworkers at Pacific Northwest National Laboratory, and who also later

were involved in development of interfaces with other CE variants, including capillary

isotachophoresis and capillary isoelectric focusing [1]

.

Fig.1. Block diagram of Capillary Electrophoresis mass spectrometry

Principle:

CEMS work by the both the principles of capillary electrophoresis and mass spectrometry. The

separated molecules are converted into ions by the interface present between the capillary

electrophoresis and mass spectrometer. Capillary electrophoresis is a separation technique which

uses high electric field to produce electro osmotic flow for separation of ions. Analytes migrate

from one end of capillary to other based on their charge, viscosity and size. Higher the electric

field, greater is the mobility. Mass spectrometry is an analytical technique that identifies chemical

species depending on their mass-to-charge ratio. During the process, an ion source will convert

molecules coming from CE to ions that can then be manipulated using electric and magnetic field.

The separated ions are then measured using a detector [1]

.

https://en.wikipedia.org/wiki/Capillary_electrophoresis

https://en.wikipedia.org/wiki/Mass_spectrometry



Capillary:

The capillary is the most important part of the system. The usual range of inner diameters is from

20–100 μm. Typically the capillaries that are used in CE are circular in cross-section. However,

capillaries with square cross-sections have been produced but to date they have not been widely

used. Capillaries were introduced into electrophoresis as an anti-convective and heat controlling

innovation. In wide tubes thermal gradients cause band mixing and loss of resolution.

Many materials have been suggested and tested for the construction of capillaries. These include

fused silica, borosilicate glass, and polytetrafluoroethylene (Teflon). Fused silica is now the

preferred material for the construction of capillaries. The silica used is of very high purity, similar

to that used to produce silicon chips for electronic components. Tubes of silica are heated to over

1000°C, and then stretched to produce the final dimensions. Fused silica capillaries are extremely

brittle. To facilitate handling they are coated with a layer of polyimide 10–25 μm thick, rendering

the capillary very flexible. The thickness of the wall of the capillary and the polyimide coating is

generally much greater than the internal diameter of the capillary. The thickness of the wall is

critical, because the heat that is produced when an electrical current passes through the electrolyte

must be removed through this wall. Reducing the wall thickness increases the fragility of the

capillary at the same time as it increases the heat transfer capacity [2]

.

Surface modifications:

The inner surface of a capillary is an extremely important factor in CEMS because the sample of

interest is in direct contact with the inner wall of the capillary. The fused silica inner wall is

naturally negative due to ionization of the free silanol groups at pH above 3.0, which then exist in

deprotonated anionic form. The ionized silica wall thus shows a tendency to interact strongly with

positively charged analytes. Such adsorption leads to fluctuation in the EOF and subsequently

irreproducible migration times, severe band broadening, low recovery, decreased sensitivity and

reduced separation efficiency. Therefore, modification of the inner wall of fused silica capillaries is

highly beneficial for reducing analyte wall interaction. Moreover, capillary wall modifications are

advantageous for alteration of the EOF to achieve rapid separation, to increase resolution,

reproducibility and to improve selectivity. In some instances, the adjustments of the pH of the

running buffer to extreme pH values that give either a highly negatively or positively charged

capillary wall were used. For instance, the electrostatic interaction of proteins with the silica

surfaces is affected by the pH. However, even if the net charge of proteins is the same as the net

charge of the capillary surface, hydrophobic domains can still interact and cause problems. In

addition, the use of pH to control such adsorption effects has in many cases some limitations, such



as protein aggregation. Other alternatives used to minimize analyte adsorption on the silica

capillaries are high-ionic strength buffers or buffer additives such as amines, low conductive

zwitterions or alkali metal salts. However, for CE-MS, high amount of salts in BGE (background

electrolyte) are not desirable as this causes loss of MS sensitivity. Additionally, high amount of

salts causes Joule heating, due to the increase in current, leading to peak distortion.

Covalent Cationic Coatings:

Covalent coupling to the ionized silanol group can be achieved either by using neutral or charged

coatings. The most commonly used are polyacrylamide (PAA) and polyvinlyalcohol (PVA). The

non-ionic nature of the neutral coating eliminates the EOF. The migration of the analytes therefore

depends only on the electrophoretic mobility, which in turn prevents detection of both acidic and

basic proteins in the same run. Other limitations include instability of the siloxane bond (Si-O-C) at

neutral pH and the coating process (silanization) is often time-consuming, involving multi-step

processes which may introduce problems with irreproducibility. The major concern is the difficulty

to regenerate the coatings, especially when dealing with complex biological samples. Such

problems can be circumvented by using charged coatings (positive or negative) covalently attached

to the silica wall, which generally give high EOF. For cationic coatings, the pH of the BGE should

generally be low, whereas for anionic coatings high pH is recommended. With many covalent

cationic coatings, the capillary can rapidly be regenerated within a few minutes by rinsing it with

the coating solution.

Electrostatic Cationic Coatings:

Non-covalent modifications are usually prepared by flushing the capillary with the adsorbed

coating reagent or by adding a certain amount to the BGE to continuously coat the capillary wall.

Different types of amines, surfactants and polymers have been applied, which are reversibly bound

to the negatively charged silica wall. Based on the type of coating used, the negative charge of a

silica surface is reduced, neutralized or even reversed. Wide variety of noncovalent coatings have

been reported that have been used successfully for CE separations including for instance;

polybrene, polyethylenimine poly (methoxyethoxyethyl) ethylenimine, poly

(diallymethylammonium chloride), Cetyltrimethylammonium bromide and polyargenine. However,

from a CE-MS perspective, the presence of additives in the BGE, or bleeding of some adsorbed

polymers, contaminate the ion source and cause ion suppression which in turn decreases the

sensitivity [3]

.



Sample Introduction Techniques:

Samples are introduced into the capillary for separation by two different methods. They are Electro

kinetic injection and Hydrodynamic (Vacuum or Pressure) Injection.

Electro kinetic injection works when the capillary is placed into the catholyte on one end and into

the analyte (containing the sample to be analyzed) on the other end. When a voltage is applied, the

EOF moves from the tip of the capillary to the end of the capillary. A siphoning effect occurs,

dragging a representative sample into the capillary. Also, ions begin moving into the capillary from

the buffer solution due to electrophoretic mobility as part of the sample loading. This can be an

advantage when trying to analyze small concentrations of these ions. These injections usually last

for 1-5 seconds.

Fig.2 Electro kinetic injection

Hydrodynamic injection works when a pressure is applied at one end of the capillary or a vacuum

is applied. The pressure differential between the two opposite sides of the capillary will make liquid

move into the capillary.

Fig.3 Hydrodynamic injection



Modes of Separation

Fig. 4 modes of separations in CEMS

Capillary Zone Electrophoresis (CZE)

CZE is characterized by the use of open capillaries and relatively low viscosity buffer systems.

Analyte molecules move from one end of the capillary to the other according to the vector sum of

electrophoresis and electroosmotic mobility. CZE is the most widespread mode of CE. It has been

used for analytes as diverse as sodium ions, drugs, and protein molecules. Analyte species can be

separated by CZE if they migrate at different velocities in the electrical field [4]

.

Fig: 5 Capillary zone electrophoresis

Capillary Gel Electrophoresis (CGE)

Capillary gel electrophoresis (CGE) is separation based on viscous drag. In this mode the capillary

is filled with a gel or viscous solution. EOF is often suppressed so that the migration of the analytes

is solely by electrophoresis. Larger molecules tend to be retarded more by the viscous separation

medium than are smaller molecules, so that the separation is effectively based on the molecular

size. This is the method of choice for molecules that differ in size. For example, DNA molecules

can vary greatly in length, but the charge per unit length is quite constant. In a pure CZE separation,

all the molecules move at very nearly the same velocity and no separation results. In a viscous

medium, the longer molecules are retarded more than shorter molecules.



Micellar Electro kinetic chromatography (MEKC)

Electrophoresis is not possible for analytes that are not charged. In order to analyze such analytes, it

is necessary to employ some agent in the separation buffer that will transport them through the

capillary. The most commonly used mode of CE for these analytes is MEKC. In this technique a

suitable charged detergent, such as SDS (sodium dodecyl sulphate), is added to the separation

buffer in a concentration sufficiently high to allow the formation of micelles. These micelles are

arrangements of detergent molecules that have a hydrophobic inner core and a hydrophilic outer

surface. Micelles are dynamic and constantly form and break apart. For any given analyte, there is a

probability that the molecules of that analyte will associate within the micelle at any given time.

This probability is the same as the partition coefficient in classical chromatography. When

associated with the micelle, the analyte molecule will migrate at the velocity of the micelle. When

not in the micelle, the analyte molecule will migrate with the EOF. Differences in the time that

analytes spend in the micellar phase will determine the separation. MEKC is useful for a wide range

of small molecules such as drugs, pesticides, and food additives that are not charged and are

sufficiently hydrophobic to associate with the micelle. While SDS is probably the most widely used

detergent for this purpose, cationic detergents such as TTAB can also be employed. Nonionic

detergents by themselves do not provide mobility to uncharged analytes, but in combination with

charged detergents they will modify the separation. Some detergents are useful in specific

applications. For example, sodium cholate is useful in the separation and analysis of a variety of

steroids. The micelles formed in this case are not the classical spherical shape but are probably

sodium cholate molecules arranged on each other like a stack of coins. Different uncharged steroids

differ in their tendencies to participate in these stacks [4]

.



Fig.6 Micellar electrokinetic chromatography

Capillary Electrochromatography

Capillary electrochromatography (CEC) is a hybrid technique between liquid chromatography and

electrophoresis. It is a partitioning technique in which molecules distribute between a stationary and

a moving phase. As described for MEKC, different analytes will tend to associate to a greater or

lesser extent with the stationary phase, effecting a separation.

CEC capillaries are packed with particles like those used in HPLC columns. Unlike conventional

LC techniques, CEC uses electroosmotic flow to drive the mobile phase down the column. The

resulting plug flow improves the separation efficiency over that of the laminar flow of pressure

driven systems. As of this writing, most of the work done on CEC has used model systems, such as

polyaromatic hydrocarbons. CEC is very useful when coupled to mass spectroscopy (CEC-MS).

Chiral Electrophoresis

Chiral molecules are molecules that can exist in two stereo-specific forms. These chiral forms or

enantiomers are identical in molecular weight and chemical formula but differ in the arrangement

of the atoms in space. Separation of these enatiomeric forms depends on the tendency to associate

differentially with other chiral molecules known as chiral selectors. By incorporating a chiral

selector into the buffer, it is often possible to separate enantiomers of a chiral molecule. The

complex of the analyte and the selector will migrate at a different rate than will the analyte alone.

Because one of the two enantiomers associates more strongly with the selector than does the other

form a separation can be achieved. The most commonly employed chiral selector is cyclodextrin,

ring shaped carbohydrates made up of 6, 7, or 8 D-glucose subunits. Cyclodextrins may be

chemically modified to alter their hydrophobicity or charge. Uncharged cyclodextrins are not

suitable for the analysis of uncharged analytes since the complex will move with the EOF.

However, cyclodextrins modified to carry a charge by addition of sulfate groups, can serve both as

chiral selectors and as carrier molecules. Other molecules, such as the antibiotic vancomycin, have

also been employed as chiral selectors.

Chiral CE can be used to separate the enantiomeric forms of pharmaceuticals as well as natural

substances, such as amino acids. Impurities as small as 0.1% is easily detected by this method.

Capillary Isoelectric Focusing (cIEF)

Molecules that carry both positively and negatively charged groups exhibit, at a specific pH, an

equal number of positive and negative charges. At this pH, known as the isoelectric pH or pI, the

molecule, although charged, behaves as if it is neutral because its positive and negative charges

cancel each other. The molecule, therefore, has no tendency to migrate in an electrical field. In



isoelectric focusing, special reagents called ampholytes are used to create a pH gradient within the

capillary. These ampholytes are mixtures of buffers with a range of pKa values. In an electrical

field, ampholytes will arrange themselves in order of pKa; this gradient is trapped between a strong

acid and a strong base. Analytes introduced into this gradient will migrate to the point where the pH

of the gradient equals their pI. At this point the analyte, having no net charge, ceases to migrate. It

will remain at that position so long as the pH gradient is stable, typically as long as the voltage is

applied. Capillary isoelectric focusing (cIEF) is used almost exclusively for the separation of

closely related protein species. Hemoglobin can be separated into several bands by this technique,

whereas separation by SDS-CGE usually results in a single form being identified. In this

application, the protein sample is mixed with the ampholyte solution and the mixture is pumped

into the capillary. When voltage is applied, the proteins and the ampholytes migrate to their

appropriate positions in the gradient.When focusing is complete, the proteins in the mixture are

distributed throughout the length of the capillary. In order to detect the proteins it is necessary to

mobilize them so that they pass by the detector in turn. There are two ways to accomplish this

mobilization. Pressure mobilization utilizes positive pressure applied to one end of the capillary to

drive the entire fluid column through the window. In order to prevent band distortion, this pressure

must be applied carefully, preferably while the voltage is still being applied. Chemical mobilization

requires that one end of the capillary be transferred to a salt solution after focusing has taken place.

Upon application of voltage, salt will migrate into the capillary, disrupting the pH gradient and

allowing the proteins to migrate past the detector by electrophoresis.

cIEF is also widely used for examining the distribution of carbohydrate isoforms of glycoproteins

[4].

Fig. 7 Capillary isoelectric focusing

Capillary Isotachophoresis (cITP)

In this technique the sample plug is introduced between two different buffers. One of these, the

leading electrolyte, has the highest mobility in the separation. The second, trailing electrolyte, has a

mobility lower than anything else does. The sign of the charge on the analytes and the buffers must



be the same. When the voltage is applied the ions in the sample form discrete zones that are not

separated into peaks; one zone is adjacent to the next. The concentration of the analyte within a

zone is constant within that zone and the length of the zone is proportional to the concentration

within the zone.Capillary isotachophoresis (cITP) of peptides and proteins has been used with MS

detection.

Fig. 8 Capillary isotachophoresis

Interfacing CE with MS

The major problem faced when coupling CE to MS arises due to insufficient understanding of

fundamental processes when two techniques are interfaced. The separation and detection of

analytes can be improved with better interface. CE has been coupled to MS using various ionization

techniques like FAB (fast atom bombardment), ESI (electron spray ionization), MALDI (matrix

assisted laser desorption/ionization) and APCI (atmospheric pressure chemical ionization). The

most used ionization technique is ESI.

Fig. 9 Interfacing CE with Electrospray ionization-MS

Electrospray ionization interface

The first CE-MS interface had cathode end of CE capillary terminated within a stainless steel

capillary. An electrical contact was made at that point completing the circuit and initiating the

electrospray. This interface system had few drawbacks like mismatch in the flow rates of two



systems. Since then, interface system has been improved to have continuous flow rate and good

electrical contact. At present, three types of interface system exist for CE/ESI-MS which are

discussed briefly [5]

.

Sheath less interface

CE capillary is coupled directly to ionization source in sheathless interface system. The capillary is

coated with conducting metal or gold or platinum wire is inserted into CE capillary to establish

suitable electrical connection. Since no sheath liquid is used, the system has high sensitivity, low

flow rates and minimum background. However, right choice of buffer solution has to be made

which is suitable for both CE separation and ESI operation.

Fig. 10 sheath less interface

Sheath Flow Interface

It is most widely used interface system. The electrical connection is established when the CE

separation liquid is mixed with sheath liquid flowing coaxially in a metal capillary tubing.

Commonly used sheath liquid is 1:1 mixture of water-methanol with 0.1% acetic acid or formic

acid. The system is more reliable and has wide selection range of separation electrolyte. There

might be some decrease in sensitivity due to sheath liquid.

Fig. 11 Sheath flow interface



Liquid junction interface

This technique uses a stainless steel tee to mix separation electrolyte from CE capillary with

makeup liquid. The CE capillary and ESI needle are inserted through opposite sides of the tee and a

narrow gap is maintained. The electrical contact is established by makeup liquid surrounding the

junction between two capillaries. This system is easy to operate. However, the sensitivity is reduced

and the mixing of two liquids could degrade separation

Mass analyzers:

Most commonly used analyzers are quadrupole analyzer, time of flight analyzer, Fourier transform

ion cyclotron resonance (FTICR).

Quadrupole mass analyzer consists four rods, opposite rods connected electrically. Only ions of a

certain mass to charge ratio will reach the detector for a given ratio of voltages, other ions have

unstable trajectories and will collide with the rods.

Time of flight analyzer determined via a time measurement. Ions are accelerated by an electric field

of known strength. The time that it subsequently takes for the particle to reach a detector at a known

distance is measured.

FTICR determining the mass-to-charge ratio (m/z) of ions based on the cyclotron frequency of the

ions in a fixed magnetic field.

Factors effecting CEMS

Some of the factors which influence the separation process by CE there by effects the analysis by

mass are given below

1. Voltage: the separation time is universally proportional to applied voltage. However an

increase in the voltage can cause excessive heat production, giving rise to temperature and

viscosity gradients in the buffer inside the capillary which causes band broadening and

decreases resolution.

2. Temperature: the main effect of temperature is observed on buffer viscosity and electrical

conductivity, thus affecting migration velocity. In some cases an increase in capillary

temperature can cause conformational changes of some proteins modifying their migration

time and the efficiency of the separation. Temperature also effects the fragmentation pattern

of the separated molecules in MS.

3. Capillary: the length and internal diameter of the capillary affects the analysis time, the

efficiency of separations and the load capacity. Increasing both effective length and total

length can decrease the electric fields, at a constant voltage which will increase migration

time. The absorption of sample components on the capillary wall limits efficiency.



Therefore methods to avoid these interactions should be considered in the development of

the separation method. This is critical in samples containing proteins. Strategies have been

devised to avoid adsorption of the proteins on the capillary wall. These strategies include

both the use of extreme pH and the absorption of positively charged buffer additives that

only require modification of the buffer composition. Other strategies include the coating of

the internal wall of the capillary with a polymer covalently bonded to the silica that prevents

interaction between the proteins and the negatively charged silica surface.

4. Buffer concentration: an increase in the buffer concentration at a given pH will decrease

electroosmotic flow and solute velocity.

5. Buffer pH: the pH of the buffer can affect separation by modifying the charge of the

analyte or other additives and by charging the EOF. For protein and peptide separation a

change in the pH of the buffer from above isoelectric point to below the pI changes the net

charge of the solute from negative to positive. An increase in the buffer pH generally

increases the EOF.

6. Organic solvents: organic modifiers such as Methanol, Acetonitrile and other are added to

the aqueous buffers to increase the solubility of the solute or other additives and or to affect

the ionization degree of the sample components. The addition of these organic modifiers to

the buffer generally causes a decrease in the EOF.

Applications:

Determination of proteins & peptides

CEMS has wide range of applications in protein analysis. Mass spectrometry combined with

capillary zone electrophoresis (CZE-MS) is widely employed for protein/peptides separation and

analysis. Some of the examples are analysis of N- linked glycopeptides, 8- aminopyrene-1,3,6

trisulfonate (APTS) labeled recombinant antibodies, apolipo proteins, bovain insulin, myoblobin,

and cytchrome C was separated by employing IT mass analyser [6]

. Hemoglobin analysed by using

CEMS was reported. Also used in determination of glycoproteins, phycobiliproteins from blue-

green algae Metal binding proteins can be analysed by using isotachophoresis as mode of

separation. Somatostatin and insulin were analysed by CZE-MALDI-MS was reported [7]

. The

analysis of carbonic anhydrase I and II in red blood cells was reported.

Determination of drugs in biological matrices

Quantitation of pharmaceutical agents in biological samples like plasma is very important in drug

discovery and development. Analysis of antiepileptic drug Lamotrigine in human plasma was

reported by Zheng et al using different BGE and sheath liquids [8]

. Anticancer drug Imatinib



analysed by CE-ESI-TOFMS with high resolution and sensitivity was reorted by Elhamili et al [9]

.

Rivastigmin in human plasma obtained from alzhemers disease patients was repoeted by employing

CZE-ESI-MS. CEMS also plays an important role in eantiomeric separation and determination.

Chiral selectors are used in this technique. Mostly used chiral selectros are cyclodextrins,

polymeric surfactants, cyclofructans, macrocyclic antibiotics, crown ethers etc. lansoprazole

analysis by CZE separation technique using β cyclodextrin as chiral selector was reported. chiral

selector hydroxypropyl-γ-cyclodextrin in order to separate the antifungal drug iodiconazole and the

structurally related triadimenol analogues with good resolution [10]

.

Human disease biomarker discovering

CE in coupling with ESI-TOF-MS was extensively applied to the identification of protein and

peptide disease biomarkers in urine. CE-ESI-TOF-MS is a proteomic approach was applied to the

analysis of specific peptide and protein patterns with the aim to identify biomarkers of

immunoglobulin A nephropathy, focal-segmental glomerulosclerosis, membrane

glomerulonephritis, lupus nephritis, diabetic nephropathy and renal transplantation diseases [11]

.

CEESI-TOF-MS was applied to the proteomic analysis of urine also in relation to cancer diseases.

22 polypeptides were identified by CE–MS as a diagnostic pattern for urothelial cancer with high

sensitivity and selectivity among the patients and healthy volunteers [12]

. Also helpful in the

biomarker discovering of muscle invasive bladder cancer. Many of the biomarkers found for

diabetes by CE–MS analysis of urine were identified as fragments of collagen type I and II,

respectively [13]

.

CEMS was also applied to the proteomic analysis of the CSF in association with Alzheimer’s

disease and schizophrenia. CE MALDI-TOF MS was used as biomarkers of neurodegenerative

diseases [14]

.

Detection of drugs of abuse in biological samples

Urine is the most commonly used biological sample for the analysis of drugs of abuse (e.g.,

amphetamines and opiates) in forensic laboratories. Morphine and related opioids detected by CE-

APEI-MS was reported. Cocaine, benzoylecgonine, cocaethylene, anhydroecgonine,

anhydroecgonine methyl ester, ecgonine methyl ester using the BGM as Formic acid (1 M) and

sheath liquid as formic acid (0.05 M) in methanol:water was reported. Plasma and serum are

typically used for emergency testing in forensics and toxicology, and in therapeutic monitoring, as

they are suitable as samples to determine the short-term use of drugs. 6-monoacetylmorphine,

morphine, amphetamine, methamphetamine, 3, 4-methyelenedioxyamphetamine, 3,4-

methylenedioxymethamphetamine, benzoylecgonine, ephedrine, cocaine analysed by



CEIT(iontrap)-MS was reported. Hair is being recognized as the third fundamental biological

specimen for drug testing. 3,4-methylenedioxyamphetamine, 3,4 methylene dioxyethyl

amphetamine, 3,4-methylenedioxymethaamphetamine methadone, cocaine, benzoylecgonine,

morphine, codeine and 6-acetylmorphine these are the few examples reported for hair analysis [15]

.

Analysis of metals, metalloids and non metals

Various forms of metals, non metals and metalloids naturally occurring in living organisms can

analysed by CEMS. Identification of manganese species in CSF was reported by Michalke et al [16]

.

Arsenic in Fish and oyster tissue, Cadmium in Rat liver, Manganese in Porcine liver, Iodine in

seaweed are some of the examples.

CEMS also useful in identification and quantification of dietary substances. For example

determination of free amino amino acids in royal jelly was reported earlier [17]

.

CONCLUSION:

CE in combination with MS has certainly emerged as an analytical tool that shows wide

applications in pharmaceutical, biological fields. It is a good alternative for widely used separation

and quantification techniques.

REFERENCES:

1. http://www.wikipedia/capillaryelectrophoresismassspectrometry.

2. Harry Whatley, Basic Principles and Modes of Capillary Electrophoresis, Clinical and

Forensic Applications of Capillary Electrophoresis Edited by: J. R. Petersen and A. A.

Mohammad, pages 26-30.

3. Anisa Elhamili, Development of Capillary Electrophoresis methods Coupled to Mass

spectrometry for Biomedical and Pharmaceutical Analysis, Uppasala Uiniversity, pages 19-

23.

4. Harry Whatley, Basic Principles and Modes of Capillary Electrophoresis, Clinical and

Forensic Applications of Capillary Electrophoresis Edited by: J. R. Petersen and A. A.

Mohammad, pages 51-54.

5. Bonvin G1, Schappler J, Rudaz S., Capillary electrophoresis-electrospray ionization-mass

spectrometry interfaces: fundamental concepts and technical developments, J Chromatogr

A. 2012 Dec 7; 1267:17-31.

6. Jianyi Cai, Jack Henion, Review on Capillary Electrophoresis- Mass spectrometry, journal

of Chromatography A, 703 (1995) 667-692.

http://www.wikipedia/capillaryelectrophoresismassspectrometry



7. Lynn A. Gennaro , Oscar Salas-Solano, Stacey Ma, Capillary electrophoresis–mass

spectrometry as a characterization tool for therapeutic proteins, Analytical Biochemistry 355

(2006) 249–258.

8. Zheng J, Jann MW, Hon YY, Shamsi SA (2004) Development of Capillary Zone

Electrophoresis-Electrospray Ionization-Mass Spectrometry for the Determination of

Lamotrigine in Human Plasma. Electrophoresis 25: 2033-2043.

9. Elhamili A, Bergquist J (2011) A Method for Quantitative Analysis of an Anticancer

Drug in Human Plasma With CE-ESI-TOF-MS. Electrophoresis 32: 1778-1785.

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Electrophoresis and Applications in Pharmaceutical, Biological and Natural Samples,

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11. S. Wittke, H. Mischak, M. Walden, W. Kolch, T. Radler, K. Wiedermann, Discovery of

biomarkers in human urine and cerebrospinal fluid by capillary electrophoresis coupled to

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(2005) 1476–1487.

12. D. Theodorescu, S. Wittke, M.M. Ross, M. Walden, M. Conaway, I. Just, H. Mischak, H.F.

Frierson, Discovery and validation of new protein biomarkers for urothelial cancer: a

prospective analysis, Lancet Oncol. 7 (2006) 230–240.

13. Claudia Desiderioa,∗, Diana Valeria Rossettib, Federica Iavaroneb, Irene Messanac,

Massimo Castagnolaa,b, Review Capillary electrophoresis–mass spectrometry: Recent

trends in clinical proteomics, Journal of Pharmaceutical and Biomedical Analysis 53 (2010)

1161–1169.

14. A. Zuberovic, J. Hanrieder, U. Hellman, J. Bergquist, M. Wetterhall, Proteome profiling of

human cerebrospinal fluid: exploring the potential of capillary electrophoresis with surface

modified capillaries for analysis of complex biological samples, Eur. J. Mass Spectrom. 14

(2008) 249–260.

15. C. Cruces-Blanco, A.M. Garcı´a-Campan˜a, Capillary electrophoresis for the analysis of

drugs of abuse in biological specimens of forensic interest, Trends in Analytical Chemistry,

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16. B. Michalke, P. Schramel, Fresenius J. Anal. Chem. 357 (1997) 594.

17. Shigeki Akamatsu *, Takao Mitsuhashi, Development of a simple analytical method using

capillary electrophoresis tandem mass spectrometry for product identification and



simultaneous determination of free amino acids in dietary supplements containing royal

jelly, Journal of Food Composition and Analysis 30 (2013) 47–51.

Documents

A REVIEW ON CAPILLARY ELECTROPHORESIS MASS …. RPA1516248015.pdf · Fig.1. Block diagram of Capillary Electrophoresis mass spectrometry Principle: CEMS work by the both the principles