Integrated optical measurement system for fluorescence spectroscopy in microfluidic channels

A transportable miniaturized fiber-pigtailed measurement system is presente d which allows quantitative fluorescence detection in microliquid handling systems. The microliquid handling chips are made in silica on silicon techn ology and the optical functionality is monolithically integrated with the m icrofluidic channel system. This results in inherent stability and photolit hographic alignment precision. Permanently attached optical fibers provide a rugged connection to the light source, detection, and data processing uni t, which potentially allows field use of such systems. Fluorescence measure ments with two dyes, fluorescein, and Bodipy 650/665 X, showed good linear behavior over a wide range of concentrations. Minimally detected concentrat ions were 250 pM for fluorescein and 100 nM for Bodipy. (C) 2001 American I nstitute of Physics.