An aptamer and hydroxyapatite-silver-zinc oxide-based novel electrochemical sensor for ultrasensitive H. pylori detection

Electrochemical biosensors offer a cost-effective way to identify Helicobacter pylori (H. pylori) (Hsp 60), responsible for stomach infections. The conductivity and surface area of the electrode were enhanced using Hap-Ag-ZnO composites on glassy carbon electrode (GCE) along with polythiophene (PP), as a conductive polymer to improve proficiency. The Hap-Ag-ZnO-PP composites have multiple functional group sites that facilitate aptamer immobilization on the GCE. This increases the sensitivity, stability, and dynamic range of the developed aptasensor. Electrochemical impedance spectroscopy, cyclic voltammetry, and square wave voltammetry were employed to examine the performance of the aptasensor. A linear behavior was observed for the modified electrode against the concentration of Hsp 60, showing a detection limit of 0.429 nM and a wide dynamic range of 0.05-300 nM. Moreover, the Hap-Ag-ZnO-PP-based aptasensor exhibits exceptional reproducibility, repeatability, fast response time (20 min), good selectivity, and excellent stability (electrochemical and storage). Therefore, the prepared sensitive aptasensor provides a promising platform for clinical diagnostics and H. pylori detection in real-world applications.