Tilted fiber Bragg grating (TFBG)-based surface plasmon resonance (SPR) biosensor

Abstract

The invention provides a tilted fiber Bragg grating (TFBG)-based surface plasmon resonance (SPR) biosensor which is characterized by comprising a broadband light source (1), a polarizing beam splitter prism (2), an optical isolator (3), a TFBG (4) coated with gold / biological adsorption layer, a reaction tank (5) and a spectrum analyzer (6), wherein the broadband light source (1) and the polarizing beam splitter prism (2) are connected with each other by virtue of an optical fiber and then are connected with the optical isolator (3); and the TFBG (4) coated with the gold / biological adsorption layer is arranged in the reaction tank (5) and is connected with the optical isolator (3) and the spectrum analyzer (6). The TFBG serves as a sensing part, and compared with a common optical fiber SPR sensor, the SPR biosensor disclosed by the invention has the advantages that the wavelength of the light source is simply changed, any mode of emitting light to a fiber core-cladding layer at different angles can be almost generated, resonance is easily realized, the resonance strength is greatly improved, and the information detection capacity is greatly enhanced; the sensitivity of the detector is greatly improved, and the detector can be used for detecting change of concentration of a solution with small biological molecules; and moreover, bovine serum albumin is adopted by the biological adsorption layer, and thus the interaction process between protein-protein and antibody-receptor biological proteins can be efficiently and accurately monitored.

Description

technical field [0001] The present invention proposes a biosensor based on Tilted Fiber Bragg Grating (TFBG) surface plasmon resonance (Surface plasmon resonance, SPR). The biosensor introduces tilted fiber Bragg grating technology and belongs to the field of optical fiber sensing technology. Background technique [0002] There is an imaginary part in the dielectric constant of metals. When light shines on the metal, according to the Gus-Hansen displacement theory, there will be evanescent waves inside the metal that travel along the inner interface; affected by external disturbances or thermal fluctuations , the surface plasmons at the metal-dielectric interface will generate collective oscillations, forming surface plasmon waves propagating forward along the metal surface. When the evanescent wave vector is equal to the surface plasmon wave vector, resonance will occur, and the reflected light energy will attenuate sharply. By observing the change of the spectral peak on t...

AI Technical Summary

Problems solved by technology

However, the SPR sensor with prism structure has the problems of large volume and complicated manufacturing process. At present, the SPR sensor produced in China can only be used in laboratories, and it is difficult to popularize it.

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