Immunosensor Based On Cladding-etched Excessively Tilted Fiber Grating Coated With Graphene Oxide

In this work, a bovine serum albumin (BSA) immunosensor based on graphene oxide (GO) modified cladding-etched excessively tilted fiber grating (ExTFG) is proposed, and the basic principle and sensing characteristics of the sensor are analyzed. Refractive index (RI) sensitivity of ExTFG is increased by 77.17% by etching its cladding diameter to 80μm. The cladding-etched ExTFG is coated with GO, and then BSA anti-monoclonal antibody (anti-MABs) are immobilized on its surface, so as to realize the special detection for BSA. Experimental results show that the sensitivity is about five times of that of the un-etched GO-coated ExTFG, the limit of detection (LOD) is ~0.165 nM by using optical spectrum analyzer with a resolution of 0.03nm.