A newly designed amperometric biosensor for the determination of ethanol through one-step electrochemical coating of (4,7-di(thiophen-2-yl)benzo[c][1,2,5]selenadiazole-co-1H-pyrrole-3-carboxylic acid) (TBeSe-co-P3CA) on a graphite electrode is presented. It was aimed to propose a newly synthesized copolymer with enhanced biosensing properties as a novel sensor for the quantification of ethanol. The conjugated copolymer (TBeSe-co-P3CA) was prepared through electrochemical polymerization by potential cycling. After polymer modification, alcohol oxidase (AOx) was immobilized on a modified electrode surface for ethanol sensing. In the analytical investigation, the calibration plot is linear above large concentration range (0.085 to 1.7 mM), where sensitivity is around 16.44 mu A/mMcm(2) with a very low detection limit (LOD) of 0.052 mM based on the signal-to-noise ratio in short response time. Moreover, interfering effect of some possible compounds were examined and the capability of the biosensor in estimating ethanol content in commercial alcoholic beverages was also demonstrated. The results showed satisfactory accuracy of the developed sensor and confirm the proposed sensor has a potential for ethanol quantification compared to the currently used techniques. (C) 2019 Published by Elsevier B.V.