Amperometric biosensors based on oxidases and PtRu nanoparticles as artificial peroxidase.

Graphical abstract Highlights • Amperometric biosensors for ethanol and methylamine detection were designed. • Yeast alcohol oxidase and methylamine oxidase were used as biorecognition elements. • Nanoparticles of PtRu as peroxidase mimetic were chosen for biosensors construction. • Both biosensors exhibit high sensitivities and broad linear ranges to the substrates. • The constructed biosensors were tested on the real samples of food. Abstract Catalytically active nanomaterials have several advantages over their natural analogues when used as artificial enzymes (nanozymes), namely, higher stability and lower cost. Nanozymes with metallic nanocomposites are promising catalysts for biosensing applications. The aim of the current research is to construct oxidase-based bioelectrodes for food analysis using nanozymes as peroxidase mimetics. Bimetallic PtRu nanoparticles (nPtRu) coupled with alcohol oxidase (AO) and methylamine oxidase (AMO) were chosen to construct amperometric biosensors (ABSs) for primary alcohols and methylamine (MA). Both ABSs show high sensitivities (336 A·M−1·m−2 for the AO-ABS and 284 A·M−1·m−2 for the AMO-ABS), broad linear ranges (25–200 µM ethanol and 20–600 µM MA) and satisfactory storage stabilities. Practical feasibility of the constructed ABSs was demonstrated on food samples. High correlation between contents of MA and ethanol in foods determined by the ABSs and reference methods was observed. [ABSTRACT FROM AUTHOR]