Non-enzyme Glucose Biosensor Based on Bimetallic Pt-Au Nanoparticles Decorated Acupuncture Needle

An electrochemical biosensor for non-enzyme glucose detection was constructed based on the synergistic action of gold (Au) nanoparticles and platinum (Pt) nanoparticles on the surface of a stainless steel acupuncture needle (AN), which was achieved by respectively electrodepositing. The functional interface (Pt/Au/AN) was characterized by a scanning electron microscope, showing that cabbage-like nanomaterials were uniformly and densely distributed on the surface of AN. Pt/Au/AN electrode also possessed outstanding electrochemical characteristics, which were studied by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Significantly, Pt/Au/AN electrode exhibited remarkably electrocatalytic activity toward glucose oxidation compared with Au/AN or Pt/AN electrode. The results indicated that the contact interface of bimetallic Pt/Au was the vital electrocatalytic site for glucose oxidation. A further study proved that the contact interface exhibited intrinsic features and distinct selectivity for sensing glucose. The prepared sensor showed a wide linear range from 0.1 to 35 mmol.L-1, and the detection limit of glucose was 0.076 3 mmol.L-1. The sensor showed great stability, excellent selectivity, and miniaturization. Furthermore, the sensor was successfully used for the detection of glucose in human serum.