▎ 摘　　要

In this study, gold nanorods (GNRs) are immobilized on the surface of fiber probe using a self-assembly method for a localized surface plasmon resonance (LSPR)-based optical fiber biosensor. In order to promote the performances of GNRs films, graphene oxide (GO) is used to encapsulate GNRs, which forms the GNRs@GO structure. Furthermore, the GNRs and GNRs@GO fiber probes are used to detect different refractive indices of surrounding environments from 1.33 to 1.38. The results show that the GNRs fiber probes have the sensitivity of 48 nm/RIU with the linearity of R-2 = 0.988. By comparison, for GNRs@GO with 0.2 mg/mL of GO fiber probe, the sensitivity is increased to 218 nm/RIU, and the linearity is improved to R-2 = 0.991. After that, anti-mouse IgG is immobilized on the GNRs and GNRs@GO fiber probes for immunoassay. The results show that the limit of detection (LOD) of GNRs fiber probe is 147.9 ng/mL, and the sensitivity is 26.5 nm/mu g mL(-1) with the linearity of R-2 = 0.936 in the detecting range of 0.1-0.5 mu g/mL. By comparison, for GNRs@GO with 0.2 mg/mL of GO fiber probe, the LOD is improved to 32.7 ng/mL, and the sensitivity as well as the linearity are increased to 61.1 nm/mu g mL(-1) and R-2 = 0.991, respectively. In addition, the optimal concentration of GO encapsulated with GNRs is 0.2 mg/mL, and the optimal response time is 20 min. The results also show that the GNRs@GO fiber probe has a good selectivity. Finally, the GNRs@GO structure shows the potential for applying in an optical fiber biosensor.