Abstract:An optical fiber biosensor based on polyaniline (PAni) functionalization was developed. Firstly, the plastic optical fiber (POF) with part of the core removed was modified using the redox reaction of aniline and APS, secondly, the optical fiber was immersed into glutaraldehyde solution for aldehyde cross-linking, again, the optical fiber was moved into AFB1 antibody solution for molecular immobilization of the AFB1 antibody, and finally, the optical fiber was immersed into bovine serum protein solution to bind the sites that were not bound to the antibody, and finally, it was placed to air-dry at room temperature. The polyaniline functionalized fiber optic biosensor can be obtained. The effects of aniline concentration and pH value on the sensitivity of the sensor were experimentally investigated, and the specificity, anti-interference and detection limit of the sensor were tested, and the theoretical model of the sensor was established. The results showed that the sensor had high selective sensitivity to AFB1 under the optimal conditions, and the output signal of the sensor had a linear relationship between the concentration and the concentration in the concentration range of 0.01~10 μg/L of AFB1, with the detection limit of 0.09 μg/L (S/N=3), which was lower than that of the national standard (0.5~20 μg/L), and the spiked recoveries ranged from 95.97%～113.13%. The recoveries were 95.97%～113.13%, and the specificity and immunity to AFB1 were good.
