Exploiting sensitive laser-induced fluorescence detection on electrophoretic microchips for executing rapid clinical diagnostics

Abstract

Fluorescence is used as a sensitive detection technique for current clinical diagnostics procedures involving slab gel separations of DNA. In transferring electrophoretic separations to smaller formats, first capillaries and then microchips, the size of the sample being separated has decreased considerably, making it necessary to routinely detect a few hundred molecules of each component in the sample. Laser-induced fluorescence detectors provide high sensitivity and can be employed in both direct and indirect modes to detect clinically relevant compounds. A number of examples show that there is no loss of clinical diagnostic capability in moving these analyses to microchip devices. Microchips also allow for parallel processing of samples by incorporating multiple channels in a single device, with a number of strategies possible for using LIF detection in these multiplex systems.