Regenerable LMR-based fiber optic immunosensor with a SnO2 metallic oxide thin film for label-free detection

This paper introduces the fabrication and characterization of a regenerable LMR-based, label-free optical fiber immunosensor. This innovative biosensor proposal was developed by functionalizing a SnO₂ metallic oxide thin film deposited on a D-shaped optical fiber using a silanization protocol. The system successfully detected IgG - anti-IgG complexes in real-time in a range of concentrations from 0.5 to 10 μg/ml and achieved a limit of detection (LoD) of 0.12 μg/ml of anti-IgG. The biosensor was extensively tested to assess its capacity for regeneration, confirming that it can be reused repeatedly, reducing the overall cost and waste typically associated with disposable sensors. This regenerability has significant implications for a range of applications, providing a more sustainable and flexible approach to biosensing technology.