Highly selective detection of ethanol in biological fluids and alcoholic drinks using indium ethylenediamine functionalized graphene

A graphene-based electrochemical sensor has been fabricated by attaching indium–ethylenediamine nanoparticles to the surface of reduced graphene oxide nanolayers. The developed screen-printed graphene ink electrode was utilized to detect and measure trace amounts of ethanol in various biological and industrial aqueous authentic samples in a cyclic voltammetry system. The combination of selective interaction between indium nanoparticles with aqueous ethanol and the large surface area provided by two-dimensional graphene layers allows the sensor to detect ethanol concentrations as low as 100 micromolar. The sensor offers a wide linear range and can generate a linear response to the increase of ethanol in the environment up to 3 molar concentrations. The selectivity of the sensor was tested and compared in response to various primary, secondary, and tertiary alcohols, where it proved to be highly selective towards ethanol. After passing standard tests, the sensor has been tested with aqueous authentic samples and was able to successfully detect and measure ethanol in urine, saliva, beer and whisk