Fumonisin B2 Standard (95%)

Investigating the binding interaction of small molecules to large ligands is a compelling task for the field of drug development, as well as agro-biotechnology, since a common trait of drugs and toxins is often a low molecular weight (MW). Here, we improve the limit of detection of the Interferometric Reflectance Imaging Sensor (IRIS), a label -free, highly multiplexed biosensor, to perform small-molecule screening. In this work, characterization of small molecules binding to immobilized probes in a microarray format is demonstrated, with a limit of detection of 1 pg/mm(2) in mass density. First as a proof of concept to show the impact of spatial and temporal averaging on the system noise, detection of biotin (MW = 244.3 Da) binding to a streptavidin-functionalized chip is performed and the parameters are tuned to achieve maximum signal-to-noise ratio (SNR approximate to 34). The optimized system is then applied to the screening of a 2,0-multiplexed antibody chip against fumonisin B1 (MW = 721.8 Da), a mycotoxin found in cereal grains. The simultaneously recorded binding curves yield an SNR approximate to 8. Five out of twenty antibodies are also screened against the toxin in a lateral flow assay, obtaining consistent results. With the demonstrated noise characteristics, further sensitivity improvements are expected with the advancement of camera sensor technology.

BACKGROUND Biosorption using agricultural by-products has been proven as a low-cost and safe way to sequester mycotoxins. Few agricultural by-products have been studied for their efficacy in adsorbing simultaneously a large range of mycotoxins. The present work compared the ability of 51 agricultural by-products to adsorb mycotoxins from liquid mediums simulating physiological pH values, and it studied the mechanism for mycotoxin adsorption by isotherm adsorption experiments. RESULTS Grape pomaces, artichoke wastes, and almond hulls were selected as promising biosorbents for mycotoxins, being quite effective towards aflatoxin B-1 (AFB(1)), zearalenone (ZEA), and ochratoxin A (OTA). Their adsorption was not affected by medium pH, and the adsorbed fraction was not released when pH rose from acid to neutral values. Fumonisin B-1 (FB1) was adsorbed to a lesser extent, and deoxynivalenol adsorption was not recorded. For the selected biosorbents, maximum adsorption capacity calculated by the best fitting model (Freundlich, Langmuir, or Sips equation) ranged from 1.2 to 2.9 mu g mg(-1) for AFB(1), 1.3 to 2.7 mu g mg(-1) for ZEA, 0.03 from 2.9 mu g mg(-1) for OTA, and 0.01-1.1 mu g mg(-1) for FB1. CONCLUSION This study confirms that some agricultural by-products can find technological applications as feed/food additives for mycotoxin reduction. (c) 2018 Society of Chemical Industry