Optical characterization of a polymer micro-optical light coupler for silicon channels

We present a micro-optical system for UV/VIS absorbance detection in silicon microfluidic channels, which consists of a micro-optical light coupler placed on top of the silicon fluidic channel to probe the molecules under test with laser light. We demonstrate the proof-of-concept of this microfluidic light probe by measuring standard samples of coumarin 102 dye with concentrations between 0.6 mu M and 6mM. Calibrating the system yields a detection limit of 4.3 mu M. To conclude, we show that the concept of this microfluidic detection system is generic in that it can be applied at different positions on different microfluidic channel configurations.