Microfluid on Chip Transesterification Reaction and Real-Time Monitor by PN Diode Photodetector

Abstract

Biodiesel is a renewable fuel made by a chemical reaction of alcohol and vegetable or animal oils, fats, or greases. Through a refinery process called transesterification. Biodiesel has been demonstrated produced by transesterification reaction by the addition of enzyme, i.e. Candida rugosa lipase [1]. In this study, we self-assemble lipase on the gold film through surface modifications. Under the gold film, a PN photodetector is pre-fabricated, and polydimethylsiloxane (PDMS) is used as a fluid channel and reaction chamber of transesterification process. Since PDMS reactor is optically transmittance, a specific wavelength of light can be used to detect transesterification reaction. The monitor for biodiesel production can be detected by means of transmittance (T %) taken as an indicator to estimate the conversion yield of the transesterification reaction. In this study, the on-chip PN diode is used as a photo detector to detect the conversion of biodiesel. As a result, the lipase-catalyzed immobilized on the Au/PN diode and a micro-fluidic device as a transesterification reaction chamber is proposed for real-time monitoring through transmittance characterization.