Modified electrochemical sensor via supramolecular structural functionalized graphene oxide for ultra-sensitive detection of gallic acid

Gallic acid (GA) is a synthetic polyphenolic compound that has been increasing interest due to its diverse biological activities, including anti-inflammatory, antioxidant, anti-tumor, scavenging free radicals, protecting cardiovascular diseases, and hypertension-lowering properties. The precise and rapid determination of GA content holds significant importance for human health. In this study, we present a cost-effective and highly sensitive electrochemical sensor employing a nanocomposite material, diester calix[4]arene functionalized graphene oxide (DEC4/GO) for the ultrasensitive detection of GA. The characterization of the as-synthesized nanocomposite material was carried out using various techniques, such as Fourier-Transform infrared (FT-IR), Raman spectroscopy, X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), and Tunneling Electron Microscopy (TEM), to ascertain its chemical composition, crystalline nature, phase purity, and structural morphology. The uniform deposition of DEC4/GO on the surface of a bare glass carbon electrode (GCE) was achieved via a drop casting method. In addition, the developed sensor DEC4/GO/GCE exhibits exceptional electrochemical response towards GA under optimized conditions, such as pH -7 phosphate-buffered saline (PBS) as a supporting electrolyte, a scan rate of 110 mV/s, and an applied potential window between −0.2 V and 0.8 V. The as-developed sensor demonstrated a wide linear dynamic range of 10–100 μM, resulting a brilliant linear calibration obtained for GA. Furthermore, the limit of detection (LOD) and quantification (LOQ) of the developed sensor were calculated as 0.01 and 0.03 μM respectively, lower than those reported for the other GA sensors. To validate the feasibility of our developed method, we analyzed the GA content in wine and green tea samples, achieving good recovery results. Overall, this study presents a promising electrochemical sensor platform for ultrasensitive detection of GA holding potential implications for various applications in health monitoring and food analysis.