A smart textile fabric-based optical nano-biosensor for hydrogen peroxide and glucose monitoring.

The incorporation of nanomaterials into smart flexible interfaces is a developing requirement for real-time diagnostics applications. In this work, we report a novel optical fabric-based sensor for the analysis of glucose and hydrogen peroxide (HO), addressing critical needs of healthcare, industrial safety, and environmental analysis. In contrast to traditional rigid substrates, we utilized cotton fabric as a porous and flexible sensing platform, immobilizing cerium oxide nanoparticles (CeO₂-NPs) using hydrogel. This method provided homogeneous nanoparticle immobilization, facilitating better analyte interaction and allowing for clear colorimetric responses. The designed sensor's mechanism is driven by the redox transition between Ce and Ce, resulting in visible colorimetric shifts upon exposure to the analyte. Additionally, the immobilization of glucose oxidase (GO) augmented the sensor's high specificity towards glucose detection. The fabricated sensor demonstrated detection limits of 0.028 mM for HO and 0.42 mM for glucose. Real sample analysis was conducted using human serum spiked with glucose, proving its analytical effectiveness. The fabric-based platform, coupled with nanoparticle and enzyme immobilization, provides a flexible, cost-effective, and scalable sensing solution for point-of-care diagnostics. This research creates a new paradigm for flexible, real-time optical sensing, enabling future innovations in smart textiles and on-the-go diagnostics.