An important capability required by many biotechnology processes is the ability to separate specific chemicals from complex biological samples and identify, quantitate and manipulate them. As a trend in biotechnology over the last decade has been the ability to work with ever small and chemically more complex samples, separation techniques such as capillary electrophoresis (CE) have been developed that work with nanoliter to picoliter volumes. However, the ability to collect and manipulate the output of small-volume separations has not kept pace with the miniaturized separation itself. The overall goal of this proposal is to develop and interface molecular gates with CE. These molecular gates will have the ability to """"""""capture"""""""" selected analytes either on-column or existing from the separation capillary for additional manipulation and analyses such as mass spectrometry and NMR. In essence, the molecular gate converts a nanoliter volume separation technique from an analytical method to a preparative method that allows manipulation of individual selected analytes. The proposed systems consists of a CE system with an imaging fluorescence detection to detect the analytes on-column, thus allowing the molecular gate to be turned on at the appropriate times to collect specific molecules. The performance of the system initially will be characterized using GABA, peptides, and DNA as model analytes. In addition to developing the CE/gate system, the capability to demount the gate and subject the analytes to assays such as mass spectrometry, nanoliter volume NMR, and PCR analysis will be developed. The ability to manipulate and identify ultra-small amounts of diagnostically useful compounds will be a significant advance for the biomedical community.