Optofluidic analysis system for ethanol solutions

We present a versatile optofluidic analysis system for non-invasive, flow-through examination of alcoholic solutions. The underlying principle is based on partial total internal reflection at the solid-liquid interface. Using an on-chip air micro-prism the laser beam is diverged, resulting in a unique reflected/transmitted light pattern depending on the solution being examined. Ethanol containing samples were passed through devices having different working ranges. Measurements between 0 and 90% ethanol were successfully conducted. Fabricated by means of rapid-prototyping techniques, the design can be customized in terms of working range as well as resolution in a cost-effective and fast manner. © 2012 Published by Elsevier Ltd.