A novel sonogel-Leucine electrochemical sensor for the detection of neuroblastoma biomarker in human urine and synthetic cerebrospinal fluid

Abstract

A new Sonogel-Carbon (SNGC) electrode modified with an amino acid ( l -leucine; Leu) has been developed for the sensitive detection of homovanillic acid (HVA). Electrochemical properties of leucine-modified Sonogel-Carbon (SNGC-Leu) were characterized using cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Comprehensive characterization using scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), Fourier-transform infrared spectroscopy (FTIR), and powder X-ray diffraction (XRD) was conducted to investigate the structure of both SNGC-Leu and SNGC electrodes. The analytical performance of the SNGC-Leu sensor including the linear response range, repeatability, selectivity, and detection limit were examined. Differential pulse voltammetry (DPV) was employed to evaluate the analytical response in a linear concentration range of HVA from 0.5 μM to 50 μM, with a detection limit of 0.4 μΜ. Satisfactory reproducibility and repeatability (coefficient of variation (%RSD) < 3.5 %) were obtained. The SNGC-Leu sensor was successfully used to detect HVA in human urine and synthetic cerebrospinal fluid (CSF), exhibiting adequate recovery rates of 97.5–102 % and 96.3–106 %, respectively. • A novel electrode based on leucine-modified Sonogel-Carbon material with renewable surface was developed and characterized. • The presence of leucine ensures improved characteristics in the electrochemical detection of HVA. • The medium nature and pH value strongly influence voltammetric responses of HVA. • The developed sensor exhibits excellent sensitivity for HVA determination, with a LOD of 0.4 μM. • The new SNGC-Leu sensor has been applied in human urine and artificial cerebrospinal fluid samples.