Development of portable and reusable optical fiber chemiluminescence biosensing platform for rapid on-site detection of Aflatoxin B1

A portable and reusable optical fiber chemiluminescence biosensing platform (OFCBP) was constructed for rapid and on-site detection of Aflatoxin B1 (AFB1) using optical fiber as biorecognition probe and chemiluminescence (CL) signal transducer. Combining with all-fiber optical structure and microfluidics injection system, the OFCBP was suitable for on-site and automatic detection of AFB1 with little sample consumption (-40.0 mu L). Based on indirect competitive sandwich-like immunoassay principle and CL signal amplifying strategy, the ultrasensitive quantification of AFB1 was achieved using OFCBP system. The affinity constant of AFB1-OVA conjugates/antiAFB1 antibody, anti-AFB1 antibody/HRP-coupled secondary antibody were determined to be 1.69 x 105 M-1 and 1.06 x 104 M-1, respectively. Under optimal conditions, the linear detection range and limit of detection of AFB1 were 0.67 - 100 ng/mL and 0.075 ng/mL, respectively, which was comparable with the reported AFB1 immunoassay methods. The robustness of the AFB1-OVA conjugates modified biosensor surface allowed multiple AFB1 bioassays with little activity loss, ensuring accurate and cost-effective detection results. The practicability and accuracy of the OFCBP fulfill the requirements of AFB1 identification in real samples by evaluating its response to various spiked water. The OFOCB system offer a reliable and convenient method for rapid on-site detection of other targets in the field of environment, food, and medical diagnosis.