Harnessing the Synergy of ZIF-67 Derived Nanohybrid-Based Immunosensing for sensitive Detection of Helicobacter pylori

Detection of Helicobacter pylori (H. pylori) infection, a significant risk factor for chronic gastritis, peptic ulcers, and gastric adenocarcinoma, poses a formidable challenge due to the lack of sensitive and selective sensing platforms. Herein, we report the synthesis of a zeolitic imidazolate framework-67 (ZIF-67) derived Co/Co₃O₄/C (CoNH) porous nanostructure, optimized for the electrochemical immunosensing of H. pylori-specific antigen VacA. By calcining ZIF-67 at elevated temperatures, we obtained CoNH with enhanced electroactivity and conductivity, crucial for signal enhancement. The synthesized CoNH was thoroughly characterized using SEM, TEM, XPS, Raman, and FT-IR techniques. Further signal amplification was achieved by introducing gold nanoparticles (AuNPs) onto CoNH-modified screen-printed carbon electrodes. Systematic investigation at each modification stage led to an optimized immunosensing platform with high sensitivity and selectivity for VacA detection. The developed immunosensor demonstrated the capability to detect low concentrations of VacA (0.1 ng/ml) within a wide linear range (0.1–50 ng/ml) with long-term stability. This highly sensitive and selective biosensor holds promise for early-stage diagnosis of H. pylori infection and gastric cancer.