Lanthanum Sulfide Nanorods Modified Glassy Carbon Electrode as Non-Enzymatic Biosensor for Xanthine

Abstract

Xanthine detection is crucial for the diagnosis of metabolic disorders like xanthinuria and gout. Xanthinuria is due to xanthine stones in the urinary tract. Earlier detection of xanthine levels in human blood can minimize the risks. In this research, a non-enzymatic xanthine sensor is fabricated by depositing different concentrations of lanthanum sulfide nanoparticles on a glassy carbon electrode (GCE). Lanthanum sulfide (La2S3) nanorods are synthesized by a simple hydrothermal method and characterized by X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDS). The effect of pH, scan rates, and xanthine concentration on the peak current is examined. La2S3-modified GCE shows good conductivity, a large surface area, fast electron transfer, and promising sensing capability for xanthine detection. The highest anodic peak for xanthine is observed at a 1 mV s−1 scan rate. The la2S3-based sensor exhibits a limit of detection (LOD) of 1.2 μM and xanthine recovery of up to 99.3%. The designed sensing system demonstrates the potential for xanthine detection in blood serum samples. The proposed sensor exhibits excellent efficiency due to fast electron transfer and good stability of La2S3 nanorods.