Colorimetric detection of aflatoxins B1 and M1 using aptamers and gold and silver nanoparticles

Mycotoxins are small molecules produced by fungi that contaminate crops and cause notable health effects for humans, owing to their inherent toxicity. Aflatoxins are among the most potent mycotoxins, with aflatoxin B1 and M1 being the most concerning. Due to their negative impact on human health and agro-economics, developing cost-effective, rapid, highly sensitive and specific detection tools is urgently needed. Nucleic acid–based synthetic receptors, aptamers, have been successfully selected for aflatoxin with high binding affinity and selectivity, and have been incorporated into a wide array of sensor platforms. By exploiting the optical properties of metallic nanoparticles, aptasensors have been developed to achieve low-cost, rapid, and sensitive tests to detect contaminated foods. Herein, we describe the use of functional nucleic acids, specifically DNA aptamers with metallic nanoparticles such as gold and silver for detecting aflatoxin B1 and M1. This review highlights various aptamer-nanoparticle assay types designed for colorimetric aflatoxin detection (i.e., solution and paper-based) along with their associated detection limits, as well as their strengths and areas for further development.