▎ 摘　　要

NOVELTY - Dual channel fiber surface plasmon resonance biosensor comprises reference channel and a sensing channel, the reference channel and the detection channel are connected by a multimode fiber. The reference channel includes a first photonic crystal fiber, and the first photonic crystal fiber is respectively fused to the multimode fiber, and the first photonic crystal fiber is coated with a silver film. The reference channel is used as a blank control to detect the amount of wavelength shift caused by non-specific adsorption. The sensing channel comprises a second photonic crystal fiber, the two ends of the second photonic crystal fiber are respectively fused with the multimode fiber, the surface of the second photonic crystal fiber is plated with a gold film, and the surface of the gold film is fixed with a graphene oxide film. The graphene oxide film is cured with an antibody film layer selectively adsorbing biomolecules or chemical components. USE - Used as dual channel fiber surface plasmon resonance biosensor. DETAILED DESCRIPTION - Dual channel fiber surface plasmon resonance biosensor comprises reference channel and a sensing channel, the reference channel and the detection channel are connected by a multimode fiber. The reference channel includes a first photonic crystal fiber, and the first photonic crystal fiber is respectively fused to the multimode fiber, and the first photonic crystal fiber is coated with a silver film. The reference channel is used as a blank control to detect the amount of wavelength shift caused by non-specific adsorption. The sensing channel comprises a second photonic crystal fiber, the two ends of the second photonic crystal fiber are respectively fused with the multimode fiber, the surface of the second photonic crystal fiber is plated with a gold film, and the surface of the gold film is fixed with a graphene oxide film. The graphene oxide film is cured with an antibody film layer selectively adsorbing biomolecules or chemical components, and the antigen corresponding to the antibody is immobilized by the gold nanoparticles during the detection process, the antibody and the antigen bind, so that the gold nanoparticles immobilized with the antigen on the surface are immobilized on the antibody film, and a coupling effect is generated between the gold film and the gold nanoparticles. An INDEPENDENT CLAIM is also included for preparing the dual-channel optical fiber surface plasmon resonance biosensor, comprising (i) preparing two-channel fiber sensor, respectively, splicing the two ends of the first photonic crystal fiber and the second photonic crystal fiber to the multimode fiber by a fusion splicer, connecting the two-stage photonic crystal fibers also by a fused multimode fiber, where the first photonic crystal fiber and the second photonic crystal fiber have a length of 0.5-2 cm, a discharge intensity of 50-100 mW during welding, discharge current of 3000- 5000 mA, and a fusion temperature of 2000-3000 degrees C; (ii) preparing a reference channel by silver mirror reaction on the surface of the first photonic crystal fiber silver plating, the thickness of the silver film is 40-60 nm; (iii) preparing of sensing channels is as follows: (a) placing gold-plated film to the second photonic crystal fiber into a vacuum ion beam sputterer, and gold-plated the surface of the second photonic crystal fiber, the current of the vacuum ion beam sputter is 5-7 mA, the time is 2-4 minutes, where the film thickness is 40-60 nm; (b) immersing fixed graphene oxide film, second photonic crystal fiber of gold plating film in 0.5-2 mmol/l 4-aminothiophenol ethanol solution for 6-24 hours to carry out surface amination of gold film and 4-aminothiophenol, attaching the molecule to the gold film through the Au-S covalent bond, and the amine group left outside to further bind to the epoxy group of the graphene oxide, washing with distilled water, immersing the second photonic crystal fiber is in 0.05 in the 1 mg/ml aqueous graphene oxide solution, placing the aqueous graphene oxide solution in an incubator at 30-60 degrees C after 20-60 minutes, evaporating the graphene oxide dispersion and realizing by physical evaporation, fixing the graphene oxide film on the surface of the gold film, where the thickness of the graphene oxide film is 0.2 to 0.6 nm; (c) immobilizing the antibody, immersing second photonic crystal fiber in 0.5-1 ml 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride at a concentration of 0.1-0.4 mol/l and 0.5-1 ml in a mixed solution of N-hydroxysuccinimide having a concentration of 0.1-0.4 mol/l after 15-60 minutes, and rinsing the distilled water; and (d) immersing in the antibody solution to be immobilized for antibody immobilization, adding the gold nano-particle immobilized antigen to the gold nano-particle dispersion having a concentration of 500-1000 ppm and a diameter of 10-50 nm, and immobilizing the antigen on the surface of the gold nano-particle by electrostatic self-assembly; and (iv) detecting antigen at 25-37 degrees C, adding human immunoglobulin solution immobilized with gold nanoparticles to a two-channel fiber SPR sensor, and resonance caused by specific binding between the antibody and the antigen immobilized by the gold nanoparticles. wavelength drift, achieving the detection of the antigen while the amount of wavelength shift caused by the specific adsorption between the actual antigen-antibody obtained based on the amount of wavelength shift of the reference channel. DESCRIPTION OF DRAWING(S) - The drawing shows a schematic representation of the dual channel fiber surface plasmon resonance biosensor.