Capillary zone electrophoresis-mass spectrometry coupling

Other Techniques. A growing technique related to lc/ms and regarded as complementary to it is that of capillary zone electrophoresis/mass spectrometry (cze/ms) (22). Using cze/ms, high resolution separation of water-soluble compounds is accompHshed by the principles of electrophoresis (qv). The sample is then coupled to the mass spectrometer by electrospray ionization (23) or a fast atom bombardment interface (fab) to produce molecular ions (24). Biotechnology applications of cze/ms have great potential (25). 

An on-line coupling of capillary electrophoresis or reversed anionic capillary isotachophoresis (CITP) with electrospray ionization mass spectrometry has been described for the separation of monophosphate nucleosides, pyridine, and flavin dinucleotides (87). The combination with CITP gives an enhancement of sample loadability and concentration sensitivity in capillary zone electrophoresis/ mass spectrometry (CZE/MS). MS-compatible buffer systems were developed (trailing electrolyte, 10 mM caproic acid pH 3.4 leading electrolyte, 7 mM HCl/ 13 mM P-alanine pH 3.9). This technique seems to be valuable for the trace analysis of DNA and RNA, e.g., to study radiation-induced DNA damage. 

Tangen, A., Trones, R., Greibrokk, T. and Lund, W. (1997) Microconcentric nebuliser for the coupling of micro liquid chromatography and capillary zone electrophoresis with inductively coupled plasma mass spectrometry. J. Anal. At. Spectrom., 12, 667-670. 

Casiot, C., Donard, O. F. X., and Potin-Gautier, M. (2002) Optimization of the hyphenation between capillary zone electrophoresis and inductively coupled plasma mass spectrometry for the measurement of As-, Sb-, Se- and Te-species, applicable to soil extracts. Spectrochim. Acta B, 57, 173-87. 

Moseley, M. A., Deterding, L. J., Tomer, K. B., and Jorgenson, J. W. Coupling of capillary zone electrophoresis and capillary liquid chromatography with coaxial continuous-flow fast atom bombardment tandem sector mass spectrometry, /. Chromatogr., 480, 197, 1989. 

For capillary zone electrophoresis (CZE) mass spectrometry coupling, another modification of an ESI interface has been developed. This interface uses a sheath flow of liquid to make the electrical contact at the CZE terminus, thus defining both the CZE and electrospray field gradients. This way, the composition of the electro sprayed liquid can be controlled independently of the CZE buffer, thereby providing operation with buffers that could not be used previously, e.g., aqueous and high ionic strength buffers. In addition, the interface operation becomes independent of the CZE flow rate. [62]... 

Vassort, A., Barrett, D. A., Shaw, P. N., Ferguson, P. D., and Szucs, R. (2005). A generic approach to the impurity profiling of drugs using standardised and independent capillary zone electrophoresis methods coupled to electrospray ionisation mass spectrometry. Electrophoresis 26, 1712—1723. 

Lee, E. D., Mueck, W., Henion, J. D., and Covey, T. R. (1989). Liquid junction coupling for capillary zone electrophoresis/ion spray mass spectrometry. Biomed. Environ. Mass Spectrom. 18, 844—850. 

Gucek, M., Vreeken, R. J., and Verheij, E. R. (1999). Coupling of capillary zone electrophoresis to mass spectrometry (MS and MS/MS) via a nanoelectrospray Interface for the characterization of some P-agonists. Rapid Commun. Mass Spectrom. 13, 612—619. 

Mccomb, M. E., Krutchinsky, A. N., Ens, W., Standing, K. G., and Perreault, H. (1998). Sensitive high-resolution analysis of biological molecules by capillary-zone-electrophoresis coupled with reflecting time-of-flight mass-spectrometry. /. Chromatogr. A 800, 1 — 11. 

Toussaint, B., Palmer, M., Chiap, P., Hubert, P., and Crommen, J. (2001). On-line coupling of partial filling-capillary zone electrophoresis with mass spectrometry for the separation of clenbuterol enantiomers. Electrophoresis 22, 1363 — 1372. 

Gottardo R, Polettini A, Sorio D, Pascali JP, Bortolotti F, Liotta E, Tagliaro F (2008) Capillary zone electrophoresis (CZE) coupled to time-of-flight mass spectrometry (TOF-MS) applied to the analysis of illicit and controlled drugs in blood. Electrophoresis 29(19) 4078 1087. doi 10.1002/elps.200800087... 

Wamke, U., Gysler, J., Hofte, B., Tjaden, U.R., van der Greef, J., Kloft, C., Schunack, W., Jaehde, U. Separation and identification of platinum adducts with DNA nucleotides by capillary zone electrophoresis and capillary zone electrophoresis coupled to mass spectrometry. Electrophoresis 22, 97-103 (2001)... 

Deforce, D.L.D., J. Raymackers, L. Meheus, F. Van Wijnendaele, A. De Leenheer, E.G. Van den Eeckhout. 1998. Characterization of DNA oligonucleotides by coupling of capillary zone electrophoresis to electrospray ionization Q-TOF mass spectrometry. Anal. Chem. 70 3060-3068. 

T Liu, XX Shao, R Zeng, QC Xia. Analysis of recombinant and modified proteins by capillary zone electrophoresis coupled with electrospray ionization tandem mass spectrometry. J Chromatogr A 855 695-707, 1999. 

Bringmann, G. et al. Analysis of the glucosinolate pattern of Arabidopsis thaliana seeds by capillary zone electrophoresis coupled to electrospray ionization-mass spectrometry. Electrophoresis, 26, 1513, 2005. 

CE provides a complementary approach to HPLC separation. It is performed in several different formats, including capillary zone electrophoresis, miceller electrokinetic chromatography, capillary gel electrophoresis, capillary isoelectric focusing, isotachophoresis, and capillary electrochromatography. Of these formats, capillary zone electrophoresis is the most popular separation technique. The most successful coupling of CE with mass spectrometry is achieved via an ESI interface. The three most practical designs are sheathless interface, sheath-flow interface, and liquid-junction interface. 

Coupling of HPLC and Capillary Zone Electrophoresis with Mass Spectrometry... 

Quantification of anthocyanins/anthocyanidins is usually performed either by UVA/ IS-spectroscopy or by HPLC with UV-detection. For qualification and structural elucidation HPLC coupled to mass-spectrometry is used. Other techniques include thin layer chromatography, gas chromatography and capillary zone electrophoresis (Figure 17). 

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