Photonic Crystal Fiber Surface Plasmon Resonance Biosensor Based on Protein G Immobilization

A gold-coated photonic crystal optical fiber (PCF) sensor has been proposed as a surface plasmon resonance biosensor. The sensor was fabricated by collapsing the holes of PCF at both ends, causing the light from the multimode fiber to reach the cladding/gold interface for surface plasmon excitation. Mixed thiol and protein G coating were employed on the gold surface, which improved the orientation of the IgG leading to enhanced performance. The sensor was able to monitor the binding kinetics of the IgG (anti-IgG) complexes and a minimum detection limit at a concentration of 0.267 mg/L of anti-IgG was found.