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 (H₂O₂), 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 Ce³⁺ and Ce⁴⁺, resulting in visible colorimetric shifts upon exposure to the analyte. Additionally, the immobilization of glucose oxidase (GO_x) augmented the sensor's high specificity towards glucose detection. The fabricated sensor demonstrated detection limits of 0.028 mM for H₂O₂ 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.