Determination of ethanol in alcoholic drinks: Flow Injection analysis with amperometric detection versus portable Raman spectrometer

Abstract

A flow injection analysis with integrated amperometric alcohol dehydrogenase biosensor and a handheld Mira-DS Raman spectrometer have been compared for the determination of ethanol in different samples of alcoholic drinks. The biosensor was constructed from the commercial screen-printed carbon electrode as amperometric transducer and covered by a thin layer comprising alcohol dehydrogenase, reduced single-layer graphene oxide, rhodium(IV) dioxide, and glutaraldehyde. Both assemblies were tested on analysis of plum brandy, white rum, vodka, white and red wines, strong dark beer, and non-alcoholic beer. The two principally different analytical methods were critically compared and some limitations found, especially in case of analysis of red wine and beers. Finally, some future improvements of both analytical tools under test outlined.