“…Recently, amperometric biosensors for CHOL analysis based on direct electron transfer (DET) between ChOx and the electrode working at low potentials have been reported [ 14 , 19 , 20 ]. It is known that nanoparticles can provide new possibilities for the construction of biosensors with excellent analytical properties due to their unique properties such as excellent conductivity, high porosity and a large surface-to-volume ratio [ 14 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 ]. It has been constructed ChOx-based biosensors where the Chox was immobilized on the surface of nanomaterials, namely, carbon nanotubes (CNTs) [ 24 ], graphene [ 25 ], metallic nanoparticles (NPs) [ 26 , 27 , 28 , 29 , 30 ], transition metals nanomaterials [ 30 , 31 ], rare earth metal oxides nanomaterials [ 26 , 30 ], conductive polymers [ 23 , 32 , 33 ], quantum dots [ 34 ], hybrid combinations of them [ 29 , 35 ] and even with redox mediators (K 4 [Fe(CN) 6 ], thionine, etc.)…”