Fig. 35. (A) Schematic representation of the immobilization of ochratoxin A (OTA) aptamers and fumonisin B1 (FB1) aptamers and their multiplex upconversion FRET between aptamer-UCNPs and GO for detecting OTA and FB1. (B) Fluorescence signal change for different mycotoxins at a concentration of 10 ng mL−1. FB1 and OTA show a significant increase in fluorescence intensity compared with other mycotoxin homologs, including AFB1, AFB2, AFG1, AFG2, fumonisin B2 (FB2) and zearalenone (ZEN), which are commonly found in foods. [Reprinted with permission from ref. 682, S. Wu, N. Duan, X. Ma, Y. Xia, H. Wang, Z. Wang and Q. Zhang, Multiplexed Fluorescence Resonance Energy Transfer Aptasensor between Upconversion Nanoparticles and Graphene Oxide for the Simultaneous Determination of Mycotoxins, Anal. Chem., 2012, 84, 6263–6270. Copyright© American Chemical Society.].
