CAPILLARY ZONE ELECTROPHORESIS WITH TIME-RESOLVED FLUORESCENCE DETECTION USING A DIODE-PUMPED SOLID-STATE LASER

A capillary electrophoresis system with time-resolved fluorescence det ection was developed using a diode-pumped solid-state laser. The laser provides 2.5-ns pulses at 349 nm with kHz repetition rates, and the G aussian-shaped beam can easily be focused to the dimensions of a capil lary. The short pulse width makes it possible to achieve nanosecond re solution and time-filtered detection. With this approach, the total si gnal from one injection can be collected and digitally processed to yi eld simultaneously ''two-channel'' data. Instrument capability is demo nstrated by resolving short-lived fluorescent interferences in biologi cal sample matrixes from long-lived fluorophores.