Graphene Oxide-Based Surface Plasmon Optical Fiber Biosensor for Thiamine Detection

The work proposes a localized surface plasmon resonance (LSPR)-based optical fiber sensor for detecting thiamine. Thiamine, commonly known as vitamin <tex-math notation="LaTeX">B₁</tex-math> , is a water-soluble vitamin that is essential for human health. It is required for the heart, muscles, and neurological system to function properly and for the metabolism of carbohydrates. Measurement of its concentration is essential in treating many diseases caused by its deficiency. The present work proposes and fabricates an optical fiber sensor for measuring its concentration in the range of 200–500 <tex-math notation="LaTeX">μ</tex-math> g/mL. The role of gold nanoparticles (AuNPs) and graphene oxide (GO) in enhancing the sensor's performance is studied. The article also describes the method involved in synthesizing and characterizing AuNPs and GO. The details of the sensor fabrication that involves the functionalization of AuNPs and GO have also been discussed along with the experimental setup. The sensitivity of the proposed sensor is found to be 0.0061 nm/( <tex-math notation="LaTeX">μ</tex-math> g/mL) with a calibration correlation factor of 0.9656 in the range of 200–500 <tex-math notation="LaTeX">μ</tex-math> g/mL.