Point of use optical sensors for the detection of mycotoxins in food: advancements and challenges

Persistent exposure to mycotoxins through consumption of contaminated agricultural produce poses serious acute and chronic health risks. Chromatographic coupled with mass spectrometric (LC–MS) technologies remain the analytical gold standard; however, their high operational and capital expenditures limit widespread deployment in resource-limited settings. Point-of-use optical sensors have thus emerged as alternatives for rapid mycotoxin screening. Sensor performance is determined by the selection or development of nanomaterial modified substrates, linker chemistries, selection and use of specific (bio)recognition elements with robust (bio)conjugation strategies. Optical transduction platforms encompass one or more of colorimetric, surface-enhanced Raman spectroscopic, near-infrared spectroscopic, localized surface plasmon resonance, or hybrid electrochemical-optical transduction platforms with suitably designed substrates and assays. However, most of these sensing systems remain at low technology readiness levels, with limited validation of reproducibility cross sensitivity and robustness. This article critically reviews advancements in mycotoxin detection, identifies translational challenges, and outlines prospects for scalable optical mycotoxin sensors.