Surface Plasmon Resonance Based Fiber Optic Dopamine Sensor Using BSA-Gold Cluster/Polymer Composites

Abstract

Highly luminescent BSA-gold clusters were synthesized and its polymer composites were prepared using PVA, PVP and PVA/PVP blend. UV-visible spectroscopy, Photoluminescence, Fourier transform infrared spectroscopy (FTIR), Transmission electron microscopy (TEM) and particle size analysis (DLS) were performed to determine the formation of gold clusters. Luminescence properties of BSA-Gold cluster and its polymer composites were evaluated and it is found that all polymers quench the fluorescence at 650 nm while PVP and PVP/PVA blend enhance the fluorescence at 450 nm. Further, a Surface Plasmon Resonance (SPR) based fiber optic sensor has been fabricated using PVP/BSA-gold clusters as the sensing material and its dopamine sensing properties were studied. The sensor shows a linear response in the range of 0 to 80 μM concentrations of dopamine and the limit of detection (LOD) of the sensor is 12 μM.