No abstract

In enzyme analysis, capillary electrophoresis (CE) offers the ease of product separation from the substrate, with the ability to use expensive reagents in microvolumes. In CE, enzymes can be measured either as mass (when they are present in high concentration) by direct light absorbency, or by catalytic activity. For example, the protease enzyme, savinase, which is used as an ingredient in washing powder, was determined directly by its absorbency at 200 nm (1). For catalytic activity measurements, the substrate, the product, or both can be measured in CE without the need for coupling reactions. Because of the increased sensitivity, most CE methods measure enzymes by their catalytic activity on a substrate. To accomplish this by CE, several approaches have been used.

Capillary electrophoresis (CE) has several advantages, such as high resolution, speed, and low cost of operation. However, it suffers from two major drawbacks: poor detection limits and matrix effects. Several approaches have been used to overcome these two problems. Here, acetonitrile stacking (AS) is presented as a simple, easy, and practical approach that can solve these two problems for many analytes, with minimum sample preparation. This laboratory successfully used AS for the analysis of several compounds by CE (1).