MoSe2-Au Based Sensitivity Enhanced Optical Fiber Surface Plasmon Resonance Biosensor for Detection of Goat-Anti-Rabbit IgG

Surface Plasmon resonance (SPR) provides an efficacious and label-free detection method for optical fiber bio-sensing. MoSe₂ is one of the transition metal dichalcogenides (TMDCs) which has broad applications in detecting specific reactions. Cysteamine hydrochloride with enriched groups can generate self-assemble films for tight attachment. In this study we aimed to combine the rapid response of optical fiber SPR sensors with the enhanced sensitivity of MoSe₂ nano-films. An optical fiber SPR biosensor with MoSe₂-Au nanostructure was proposed and implemented, and a sensitivity of 2821.81 nm/RIU was achieved, which was approximately 98.7% higher than that of conventional SPR sensor without using MoSe₂ nanostructure. Furthermore, Bovine Serum Albumin (BSA) was utilized as the target molecule to test the bioaffinity of the biosensor with MoSe₂ deposition cycles from 0 to 8. Weighing the sensitivity and the figure of merit (FOM), the best deposition cycle of MoSe₂ was 4 with the sensitivity of 2793.36 nm/RIU and FOM of 37.24 RIU⁻¹. At last, immunization experiments were carried out using Goat-anti-Rabbit IgG and a detection limit of <inline-formula> <tex-math notation="LaTeX">$0.33~\mu \text{g}$ </tex-math></inline-formula>/mL was achieved. The rapid response and the high bioaffinity showed a strong applicability of the proposed MoSe₂-Au SPR immune-sensor in specific interactions and immunization therapy.