Chemiluminescence detection in capillary electrophoresis

Table 2 Applications of Chemiluminescence Detection in Capillary Electrophoresis... 

A.M. Garcia-Campana, L. Gamiz-Gracia, W.R.G. Baeyens and F.A. Barrero, Derivatization of biomolecules for chemiluminescent detection in capillary electrophoresis. J. Chromatogr.B 793 (2003) 49-74. 

Chemiluminescence detection in capillary electrophoresis (CE) has attracted much attention as a promising way to offer excellent analytical selectivity and sensitivity. Several reagents, such as luminol, acridinium, peroxyoxalate, and tris(2,29-bipyridine)ruthenium(II) complex have been utilized. Since chemiluminescence detection is approximately 102—106 times more sensitive than spectrophotometric and fluorometric detections, its combination with isoelectric focusing may result in a highly sensitive analytical tool for amphoteric compounds, e.g., proteins and peptides. A detector using luminol-H202 chemiluminescence has been characterized in a very simple and inexpensive setup, but only pressure-driven mobilization of the zones was effective. [68],... 

AM Garcia-Campana, WRG Baeyens, NA Guzman. Chemiluminescence detection in capillary electrophoresis. In AM Garcia-Campana and WRG Baeyens, eds. Chemi-luminescence in Analytical Chemistry. New York Marcel Dekker, 2001, pp 427-472. 

Huang, X. J. and Fang, Z. L., Chemiluminescence detection in capillary electrophoresis. Anal. Chim. Acta, 414,1, 2000. 

Zhu R and Kok WTh (1998) Post-column derivatization for fluorescence and chemiluminescence detection in capillary electrophoresis. Journal of Pharmaceutical and Biomedical Analysis 17 985-999. 

Wang X, Bobbitt DR (1999) In situ cell for electrochemically generated Ru(bpy)3 -based chemiluminescence detection in capillary electrophoresis. Anal Chim Acta 383(3) 213-220... 

Staller, T.D. Sepaniak, M.J. Chemiluminescence detection in capillary electrophoresis. Electrophoresis 1997, 18, 2291. 

Figure 2 Number of papers that have been published (by mld-2003) on various chemiluminescence reactions used for detection In capillary electrophoresis.

Mangru, S.D., Harrison, D.J., Chemiluminescence detection in integrated postseparation reactors for microchip-based capillary electrophoresis and affinity electrophoresis. Electrophoresis 1998, 19(13), 2301-2307. 

Hashimoto, M., Tsukagoshi, K., Nakajima, R., Kondo, K., Chemiluminescence detection in microchip capillary electrophoresis. Chem. Lett. 1999, 781-782. 

Detection of the molecules produced, consumed, and secreted by the cells described here is challenging for two main reasons. First, the cell is dynamic and constantly tries to maintain balance. As such, molecules concentrations or speciation are usually changing. Second, the matrix in which these measurements are typically performed is very complex. Thus, the technique of choice needs to have some built-in feature that enables the analyst to overcome the matrix. To date, a variety of measurements have been employed to learn more about the roles of the cells in the microcirculation. Specifically, fluorescence, chemiluminescence, and amperometry have all been used extensively. Not surprisingly, all three of these detection schemes are readily employed in capillary electrophoresis-based determinations. Therefore, many of the measurements employ technology from the CE field. However, due to the cell matrix complexity, techniques are required to overcome potential interfer-ents. Eor example, Kovarik et al. employed a Nafion coating over a micromolded ink electrode for selectivity in detecting dopamine in the presence of an anion interferent (ascorbate). Eor similar reasons, Ku" ° employed the classic method of multiple standard additions to quantitatively determine the amount of NO released from activated platelets in a flowing stream. 

Since the first publication by Hara and co-workers in 1991, most of the analytically important chemiluminescent reactions have been employed for detection with capillary electrophoresis, as shown in Figure 2. Although chemiluminescence is an attractive mode of detection for capillary electrophoresis, interfacing the detection system with the electrophoretic separation is more complex than with HPLC. Nevertheless, a number of chemiluminescence detectors have been developed and successfully employed for the... 

Kuyper C, Milofsky R (2001) Recent developments in chemiluminescence and photochemical reaction detection for capillary electrophoresis. TrAC Trends Anal Chem 20(5) 232-240. doi 10.1016/S0165-9936(01)00066-8... 

Luminol-based chemiluminescence methods have also been employed for detection of analytes in flowing stream analytical techniques such capillary electrophoresis (282), flow injection analyses, and hplc (267). AppHcations of the enhanced luminol methodology to replace radioassay methods have been developed for a number of immunological labeling techniques (121,283). 

As can be seen in Table 3, a wide range of analytes derivatized with different labels have been detected using the POCL reaction. Most of these applications have employed flow injection or liquid chromatographic techniques. An area of growing interest is the combination of capillary electrophoresis with chemiluminescence. Several strategies have been used to detect analytes with fluorescent... 

Liu, B. R, Ozaki, M., Utsumi, Y, Hattori, T, and Terabe, S. (2003). Chemiluminescence detection for a microchip capillary electrophoresis system fabricated in poly(dimethylsiloxane). Anal. Chem. 75, 36-41. 

Yang, W.P., ZJ. Zhang, and W. Deng. 2003. Speciation of chromium by in-capillary reaction and capillary electrophoresis with chemiluminescence detection. J. Chromatogr. A 1014 203-214. 

Due to its simple optical devices, wide linear range of response and many well characterized CL systems, chemiluminescence (CL) is uniquely suited to on-line detection for /t-TAS. Some reports have shown that CL is an alternative promising detection method for capillary electrophoresis microchip. In the present work, some glass microchips were designed based on the flow injection and electroosmotic flow (EOF)-chemiluminescent devices and applied to determine transition metal ions and organic compounds. 

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