Biosensors for Aflatoxins Detection

The availability of rapid and reliable methods for rapid determination of small molecules, as contaminants in food samples, including Aflatoxins, is an increasing need also for human health. In order to monitoring food contaminants, as Mycotoxins (MTXs) Gas Chromatographic (GC) and High Pressure Liquid Chromatography (HPLC) methods are generally utilized, due to their high detection sensibility and selectivity. However, GC and HPLC analyses are time consuming and needs sample pre-treatment or pre-concentration procedures. Immunoassays and biosensors are becoming a recognized alternative or complementary to conventional analytical techniques for the detection of mycotoxins, as Aflatoxins. Recently, biosensors based on the use of monoclonal or polyclonal antibodies have seen a great development in the field of small molecules analytical determination and specifically in the mycotoxins analyses. Among biosensors for mycotoxins monitoring, optical or electrochemical devices for Aflatoxins detection were described by different authors. The present Chapter describes the different biosensors for Aflatoxins developed and utilized in food analysis. The absence of cross-reactivity obtained with most of these biosensor, the possibility of on-line measurement, the absence of sample pre-treatment, can really put it in competition with other conventional systems such as HPLC and ELISA. Chapter describes also main biosensors features and vantages for these innovative devices and various examples of biosensors and reviews some biosensors for Aflatoxins and other mycotoxins detection methods, as microarray. In particular, we will focus our attention on biosensors developed for mycotoxins detection that utilize immunoglobulins or aptamer showing affinity for a correspondent analyte, associated to various transduction elements. Various biosensing platforms will be introduced, including, but not limited to, surface plasmon resonance and quartz microbalance crystals. Examples of biosensors array, as microarray, detecting Aflatoxin and Fumonisin will be also presented. Some of these biosensing devices were developed in our laboratories and the sensing performance of each device will be evaluated and compared in terms of sensitivity and detection limit. Analytical methods used for mycotoxins determination are mainly based on TLC, HPLC or ELISA. Actually biosensor and microsystem technologies are used for different applications including studies of human and veterinary diseases, drug discovery, genetic screening, clinical and food diagnostics. According to these approaches the aim of many authors was to transfer the methods of the immunological assay from microtiter plates into a biosensor format in order to develop a rapid, sensitive and inexpensive method for the detection of