EVALUATION OF A CAPILLARY ELECTROPHORETIC METHOD FOR RAPID SCREENING OF SINGLE-COMPONENT COMBINATORY LIBRARIES

The potential utility of capillary electrophoresis (CE) as an analysis and biological assay method for rapid screening of single-component c ombinatory libraries is demonstrated by mimicking a 5 x 5 drug matrix. Twenty-five compounds (some drugs, vitamins, metabolites, etc.) that include biotin are selected as the test analytes and avidin is treated as the biological activity screening reagent. In order to rapidly scr een the compounds, five mixtures of nine components each are created a t the diagonal of the matrix by pooling each component from the same c olumn and row. The separation power of CE and related techniques is su ch that the components in these randomly generated nine-compound mixtu res are almost always resolved using a single logical set of separatio n conditions. After obtaining optimum separation conditions, affinity testing produces the locations of the possible active component(s) bas ed on changes in peak area. Blind tests are conducted that successfull y locate the active component(s) of the matrix. With each test requiri ng about 14 separations (7 with and 7 without avidin) and each separat ion within 15 min, we were able to analyze the mixture and identify th e exact locations of two possible active compounds (biotin and an unex pected compound) in the 5 x 5 matrix. The effect of avidin concentrati on on the screening procedure is assessed. Another protein, myglobin, was tested to compare specific and nonspecific interactions and to ass ign a threshold value (percent decrease in peak area) for determining a positive affinity response. (C) 1998 John Wiley & Sons, Inc.