Nano-enhanced Fiber SPR Sensor Biodetection Technolog

Optical fiber surface plasmon resonance technology is used to analyze the interaction between molecules,which has high reliability and accuracy in the detection of biomolecules.However,the traditional optical fiber SPR sensor still has some defects in biological detection,such as low sensitivity and poor signal-to-noise ratio.In order to solve the problem of low sensitivity,this paper introduces nano-materials to improve and optimize the optical fiber SPR sensor,and proposes a nano-enhanced SPR biosensor,which can realize the specific identification and detection of micro-pathogens and the enhancement of biological signals.In this paper,an optical fiber SPR sensor based on graphene oxide is constructed.Using the characteristics of graphene oxide with high conductivity and large specific surface area to bind more biomolecules,it is used in the refractive index detection experiment of sodium chloride solution,and the test sensitivity is improved to 2844.15nm/RIU.Using this sensor to detect concanavalin concentration,the results show that the sensor can be applied to the biological field and can realize high sensitivity detection.Based on these results,in order to further improve the sensitivity of the sensor,the modified graphene oxide fiber-optic SPR sensor is used as the sensing platform,and the conjugate of gold nanoparticles and antibodies is added to make it continue to combine with the antigen on the sensor surface,so as to realize the secondary enhancement of the SPR signal and effectively improve the performance of the traditional fiber-optic SPR sensor.The results showed that it could detect Escherichia coli with concentrations of 1?10~3 to 1?10~7 CFU/m L,and the detection limit was 142.4 CFU/m L.Compared with direct detection,the detection limit was changed from 8.351?10~6CFU/m L to 142.4CFU/m L,and the sensitivity was greatly improved.This nano-enhanced optical fiber SPR biosensor based on graphene oxide can detect Escherichia coli with high sensitivity,better selectivity and repeatability,and can be widely used in other biomedical detection fields.