Titanium Dioxide-Graphene–Black Phosphorus-Based SPR Sensor for <i>Helicobacter pylori</i> Bacteria Detection

Abstract

Helicobacter pylori plays a significant role in the development of various gastrointestinal diseases. It is a form of bacteria that infects the first part of the small intestine (duodenum). This bacterium is a common cause of peptic ulcers. This article presents two surface plasmon resonance (SPR) sensors for the detection of H. pylori. Sensors 1 and 2 consist of a structure of prism-Ag–TiO2–graphene-BP–SM and prism-Au–TiO2–graphene-BP–SM, respectively. This work takes advantage of the excitement of surface plasmons and evanescent waves at the metal-dielectric interface. The angular interrogation technique is used to analyze the proposed sensors at a wavelength of 633 nm. Results show that sensor 1 furnishes the maximum sensitivity of 321.43°/RIU, quality factor (QF) of 57.09 RIU-1, dip of figure of merit (DFoM) of 5974.53, and combined sensitive factor (CSF) of 52.63, and sensor 2 endows the maximum sensitivity of 261.25°/RIU, QF of 30.41 RIU-1, DFoM of 22, 139, and CSF of 28.21. The results furnish a substantial improvement in comparison to the reported work in the literature. Finally, the field distributions of the proposed sensor are exhibited using the COMSOL software.