Monitoring of enzymatic reactions using conventional and on‐chip capillary electrophoresis with contactless conductivity detection

Abstract

The use of CE with contactless conductivity detection was evaluated for monitoring enzymatic reactions. The nonionic species ethanol, glucose, ethyl acetate, and ethyl butyrate were made accessible for analysis by CE via charged products or by-products obtained in enzymatic conversions using hexokinase, glucose oxidase, alcohol dehydrogenase, and esterase. Two of the reactions, namely the conversion of glucose with glucose oxidase and that of ethylacetate with esterase, were also successfully demonstrated on a microchip device. Quantification for ethyl acetate, taken as an example, was found possible with a detection limit of approximately 7 microM.

Applications of capillary electrophoresis with capacitively coupled contactless conductivity detection (CE‐C4D) in pharmaceutical and biological analysis

“…Conventional CE and MCE with C 4 D were evaluated for monitoring enzymatic reactions (Schuchert‐Shi et al. , 2007, 2008). The nonionic species ethanol, glucose, ethyl acetate and ethyl butyrate were made accessible for analysis by CE.…”

Following the lipase catalyzed enantioselective hydrolysis of amino acid esters with capillary electrophoresis using contactless conductivity detection

“…The nonionic species glucose, ethanol, ethyl acetate, and ethyl butyrate were made accessible for analysis by CE via charged products or byproducts obtained in enzymatic conversions using hexokinase, glucose oxidase, alcohol dehydrogenase, and esterase, respectively. 18 Recently, urea was also determined by CE-C 4 D in clinical samples via enzymatic conversion to ammonium ion with urease. 19 The application of CE-C 4 D to the monitoring of the lipase-catalyzed hydrolysis of amino acid esters is reported herein.…”

Development and Validation of a Chromatographic and Electrophoretic Method for the Determination of Amikacin and Urea in Bronchial Epithelial Lining Fluid

“…Quantification was carried out by conductivity measurement. The use of CE-C 4 D for the monitoring of enzymatic reactions has been demonstrated for conversions of ethanol, glucose, ethyl acetate and ethyl butyrate [30]. Enzymatic conversion of urea to ammonium by conventional or microchip CE-C 4 D has also been described [31].…”