Template-free growth of copper-doped hydroxyapatite nanowhiskers and their use as uric acid electrochemical sensor

Abstract

We synthesize copper-doped hydroxyapatite (Cu HAp) bioceramic nanowhiskers (aspect ratio ˃ 85) by a surfactant-free hydrothermal route. The detailed structural and compositional characterizations confirm the existence of catalytic multivalent Cu 1+ /Cu 2+ dopant ions and secondary β TCP phase. The dopant-induced oxygen vacancies promote active sites on the mesoporous surface (specific area ~ 60.4 m 2 /g) for electrochemical applications. The electrochemical studies of the fabricated Cu HAp FTO revealed good response, sensitivity and stability towards uric acid (lowest stable detection limit ~0.5 μM) in the lower and higher concentration regimes respectively. Thus, our fabricated Cu HAp shows surface-dependent electrochemical activities and non-enzymatic selective response to uric acid. Novel nanowhisker shaped mesoporous copper-doped hydroxyapatite has been employed for catalytic activity and sensing. Three electrode-based non-enzymatic electrochemical sensing of uric acid has been studied by voltammetry and amperometry. Multivalent dopant-induced oxygen vacancies and presence of secondary phase regulates the active sites on the whisker surface. • Copper-doped hydroxyapatite synthesis by surfactant-free hydrothermal route. • Novel mesoporous nanowhisker-shaped morphology of high specific surface area. • Multivalent doping induced oxygen vacancies promote active sites on surface. • Stable eco-friendly non-enzymatic electrochemical sensor of uric acid. • Good sensitivity, selectivity, fast response and reproducibility is achieved.