Development of non-enzymatic cholesterol bio-sensor based on TiO2 nanotubes decorated with Cu2O nanoparticles

Graphical Abstract. (a) Schematic of electrochemical oxidation of cholesterol at the surface of Cu2O NPs decorated TNTs electrode, (b) amperometric response of TNTs and Cu2O decorated TNTs. [Display omitted] •We present an efficient, simple and cost effective approach to produce highly sensitive non-enzymatic biosensor for cholesterol detection.•Sonication assisted chemical bath deposition technique is employed for the decoration of anodic TiO2 nanotubes (TNTs) with Cu2O nanoparticles (NPs).•The fabricated electrode exhibited higher oxidation current towards cholesterol oxidation and offers a 5-fold increase in sensitivity and quick response time (3 s) as compared to the pristine TNTs.•The excellent selectivity of TNTs decorated with Cu2O NPs for cholesterol detection and stability study illustrates its potential use in real physiological conditions.•The real time analysis of the modified electrode for cholesterol detection in human blood serum shows comparable values to the commercially available enzymatic sensors and can further be utilized for clinical sample detection. A novel amperometric non-enzymatic cholesterol biosensor based on Cu2O-TiO2 hybrid nanostructure has been studied. TiO2 nanotubes (TNTs) were synthesized via anodization of titanium (Ti) foils and subsequently decorated with Cu2O nanoparticles (NPs) using chemical bath deposition (CBD) method. Incorporation of Cu2O NPs on TNTs have resulted in the high electroactive surface area which enhanced the electron transfer rate at the surface of the electrode. Cyclic voltammetry (CV) and amperometric response of the fabricated electrode exhibited high catalytic activity towards the cholesterol oxidation. The hybrid electrode demonstrated 5-fold increase in the sensitivity (∼6034.04 μAmM−1 cm−2) compared to pristine with low detection limit (∼0.05 μM) and fast response time (3 s). Moreover, the real time analysis of the cholesterol in human blood serum offered favorable accuracy with reference to the commercially available cholesterol biosensors. This study shows potential application of Cu2O NPs decorated TNTs for the development of highly stable, reproducible, and selective biosensor.