Amperometric biosensors based on alcohol oxidase and peroxidase-like nanozymes for ethanol determination

The aim of the current research is to design alcohol oxidase-based amperometric biosensors (ABSs) using hybrid metallic nanoparticles as artificial peroxidases (PO) or PO-like nanozymes (NZs). A lot of metallic PO-like NZs were synthesized and tested with respect to their ability to substitute natural PO in solution and on amperometric electrode. The most effective PO mimetics were coupled with alcohol oxidase (AOX) on graphite electrodes (GEs) and characterized. Two types of modified GEs, namely, the AOX/nAuCePt/GE and the AOX/nFePtAu/GE show the highest sensitivities to ethanol (2600 A.M-1.m(-2) and 1250 A.M-1.m(-2), respectively), low limits of detection (1.5 mu M and 2.2 mu M), broad linear ranges (5 - 100 mu M and 12 - 120 mu M), as well as satisfactory storage stabilities. The most sensitive bioelectrode AOX/nAuCePt/ GE was used as ABS for ethanol determination in real samples. The practical feasibility of the constructed ABS was demonstrated by determination of ethanol in beverages, human blood and saliva.

Automated summary

The aim of this research is to design alcohol oxidase-based amperometric biosensors using metallic nanoparticles as artificial peroxidases or peroxidase-like nanozymes. Various metallic peroxidase-like nanozymes were synthesized and tested for their ability to replace natural peroxidase. The most effective nanomaterials were coupled with alcohol oxidase on graphite electrodes and showed high sensitivities and low limits of detection for ethanol, as well as satisfactory storage stabilities. The bioelectrode with the highest sensitivity was used as a biosensor for ethanol determination in real samples, demonstrating its practical feasibility.