A portable optical fiber biosensor for the detection of zearalenone based on the localized surface plasmon resonance

With the continuous improvement of people?s living standards, food safety issues have gradually become one of the main concerns. Rapid and accurate detection of zearalenone (ZEN) in food has attracted broad research interest. In this work, a low-cost, portable, and reusable optical fiber-based localized surface plasmon resonance (LSPR) biosensor for ZEN was developed. Gold nanoparticles around 25 nm were synthesized and coated on the cross-section of the end of an optical fiber, and then the ZEN nucleic acid aptamer was modified to form the LSPR biosensor for ZEN detection. Results showed that there was a good relationship between ZEN concentrations and the redshifts of LSPR peak in the range of 1 similar to 480 ng/mL, the limit of detection was 0.102 ng/mL. Moreover, the sensing interface could be easily regenerated by cutting and polishing the end of the optical fiber, indicating that the LSPR biosensor was reusable. It also has exceptional high selectivity for ZEN and good recovery and repeatability, which has a good prospect for the on-site ZEN monitoring.