Colorimetric sensors fo aflatoxins detection

Abstract

Aflatoxins comprise a group of toxic compounds produced by Aspergillus fungi in oilseed grains and pose a health risk. Anthocyanins are natural phenolic compounds capable of indicating the presence of aflatoxins through color changes. The objective of this proposal is to explore the colorimetric potential of anthocyanins and the filmogenic potential of micro- and nanofibrillated and bacterial cellulose to produce colorimetric sensors for the detection of aflatoxins. To this end, it is proposed to incorporate anthocyanins into micro- and nanofibrillated cellulose films and bacterial cellulose membranes. Materials with different compositions and concentrations of anthocyanins will be studied, seeking to optimize their sensory capacity, according to the intensity of color change in the presence of aflatoxins and the time for this to occur. The micro- and nanofibrillated cellulose films, precursors to colorimetric sensors, will be obtained via continuous casting, a pre-industrial scale technique for producing films from polymeric solutions. The materials obtained will be characterized by infrared techniques in ATR mode, X-ray diffraction, water vapor permeability, mechanical tensile tests, film solubility in water, static contact angle, thermogravimetry, exploratory differential calorimetry, response time, minimum detectable concentration of aflatoxins, sensory evaluation with volunteers, scanning electron microscopy and biodegradability tests.