Self-assembled 3D/0D quasi-core-shell sensitized optical fiber biosensor for ultrasensitive detection of Helicobacter...

Early detection of Helicobacter pylori (H. pylori) infection is crucial for preventing cancer development. However, current diagnostic methods are limited by prolonged diagnostic processes, insufficient sensitivity, and restricted patient applicability. In this study, a self-assembled 3D/0D quasi-core-shell material, AuNPs@ZIF-90-COOH (Au@ZIF-C), was developed, which exhibits excellent photoelectric properties, high antibody-loading capacity, and favorable biocompatibility. Subsequently, Au@ZIF-C was utilized to enhance the surface plasmon resonance (SPR) spectral response, enabling the design of an optical fiber biosensor for ultrasensitive H. pylori detection. This sensor achieved the sensitivity of 1.465 nm·(lg CFU/mL)^-1 with the response time of 16 s, and the detection limit of 1.37 CFU/mL. Furthermore, analysis of gastric juice samples demonstrated its significant diagnostic potential for clinical applications. This work presents a novel strategy that employs 3D/0D quasi-core-shell materials to enhance the performance of optical fiber biosensors, facilitating rapid and highly sensitive target detection with considerable promise for microbial diagnostics.