Monitoring photopolymerization of caffeic acid using a UV-C pulsed light generator and silicon photomultiplier

Abstract

The photopolymerization of caffeic acid (3,4-Dihydroxy-trans-cinnamate) was triggered using pulses of UV-C light at 278 nm during which the fluorescence of caffeic acid was measured and can be considered as an indicator for this pho-topolymerization process. We present a technological approach and evaluate the fluorescence signal of caffeic acid excited by pulses of UV-C radiation using a silicon photomultiplier SiPM in Geiger mode. Furthermore, liquid chromatography - mass spectrometry (LC-MS) analysis showed that a dimer of caffeic acid was successfully photodimerized.