CuCoP@Cu(OH)2 core-shell nanostructure as a robust electrochemical sensor for glucose detection in biological and beverage samples

Abstract

The direct growth of transition metal phosphides with a highly accessible surfaces and copper electroactive centers can be considered as an efficient method to modify the electrode surface and use them as an electrochemical sensor. Herein, a direct, efficient, low-cost and rapid method is used for growing core–shell nanostructures of CuCoP nanosheets on Cu(OH)2 nanotubes (pre-deposited on glassy carbon electrode). The Cu(OH)2 nanotubes act as a conductive intermediate and directing agent to obtain CuCoP@Cu(OH)2 core–shell structure. The growth of CuCoP on Cu(OH)2 nanotubes provides structural stability and large surface area as well as increases the availability of the catalytic sites for diffusion of analyte species and electrolyte ions into the electrode surface, leading to excellent electrocatalytic performance towards glucose electro-oxidation. The amperometric studies of glucose for electrode modified with CuCoP@Cu(OH)2 showed two linear ranges of 0.001 mM to 0.105 mM and 0.105 mM to 2.530 mM with very high sensitivities of 8351 and 3932 μA/mM.cm2, respectively. Also, the fabricated sensing platform exhibited excellent selectivity and resistance to chloride ion poisoning, good reproducibility and repeatability, as well as low detection limit of 2.3 μM. In addition, the modified electrode showed a very quick reaction time of 2 s. Finally, to assess the usability of the designed non-enzymatic sensor in practical applications, the as-prepared nanocomposite was examined for measuring the glucose content in biological samples such as human blood serum, saliva, and beverage samples. The outcomes showed that the designed platform can be used as a reliable and efficient sensor for accurate detection and measurement of glucose in real samples.