Electrodeposited Ni on a silk-derived carbon modified glassy carbon electrode for non-invasive sensing of glucose in saliva

Abstract

In order to improve the life quality of diabetic patients, a groundbreaking study has designed a non-invasive sensor capable of monitoring glucose levels in saliva. The non-enzymatic glucose sensor constructed through electrodeposition of Ni represents an innovative electrochemical sensor aimed at enhancing the sensitivity and stability of glucose detection, while addressing the limitations of enzyme activity in traditional enzymatic sensors. This sensor is realized by loading a layer of nickel (Ni) electrodeposited on silk-derived carbon on the electrode surface. Nickel, as a catalyst, can directly catalyze the oxidation of glucose, generating a current signal proportional to the glucose concentration. In this non-enzymatic detection system, electrodeposition technology allows precise control over the structure of the nickel layer, optimizing its electrochemical activity and stability. Such nickel-based electrodes exhibit excellent catalytic efficiency and reusability, which is crucial for the development of reliable blood glucose monitoring devices. The non-enzymatic glucose sensor demonstrates an outstanding sensitivity of 484.22 μA mM⁻¹ cm⁻², a wide linear range of 1–1498 μM (1st linear range), and a low detection limit of 0.16 μM (S/N = 3). Furthermore, it shows excellent selectivity, stability, and fast response time for glucose. Importantly, the developed non-enzymatic glucose sensor can detect glucose levels in human saliva without any pretreatment, showing great potential for application in non-invasive sensors. By adjusting the electrodeposition parameters, such as deposition voltage, time, and nickel salt concentration, the surface morphology and structure of the nickel film can be further tuned to meet various detection requirements. The prepared sensor has great potential for application in clinical and personal health monitoring.