Nanochemistry and nanotechnology

Smartphone sensor systems for aflatoxin B1 and zearalenone detection based on nanostructured polymeric membranes
Sergeyeva T.A. 1, Yarynka D.V.1, Dubey I.Ya.,1 Dubey L.V.,1 Piletska O.V.,2 Linnik R.P.,3 Zaporozhets O.A.,3 Piletsky S.A.,2 Brovko O.O.,4 El’skaya A.V.1
1 Institute of Molecular Biology and Genetics, Natl. Acad. of Sci. of Ukraine. Zabolotnogo str., 150, Kiev-03680, Ukraine. 
E-mail: t_sergeyeva@yahoo.co.uk
2 University of Leicester, LE1 7RH,  Leicester, UK.
3 Taras Shevchenko National University of Kyiv, Department of Chemistry, 64/13 Volodymyrska Street, 01601, Kiev, Ukraine.
4 Institute of Macromolecular Chemistry, Natl. Acad. of Sci. of Ukraine. Kharkivske shosse, 48, Kiev-02160, Ukraine.

Novel smartphone-based fluorescent sensor systems based on nanostructured molecularly-imprinted polymer (MIP) membranes for selective recognition of widespread food toxins aflatoxin B1 and zearalenone were developed for rapid and sensitive point-of-care detection of these analytes in food stuffs. The developed MIP membranes were capable of highly-selective recognition of the target analyte and generation of an optical sensor response, which could be registered using the camera of a smartphone and analysed using image analysis. The MIP membranes were synthesized in situ using fragment-based approach taking into account data of computational modelling. UV irradiation of the mycotoxins, selectively bound by artificial binding sites in the MIP membranes from the analysed samples, initiated their natural fluorescence with intensity directly proportional to their concentration. Two functional monomers (acrylamide and ethyleneglycolmethacrylate phosphate) were identified as optimal for the formation of aflatoxin B1- and zearalenone-selective binding sites in the MIP membranes, respectively. The smartphone-based sensor system provides a possibility of synchronous detection of aflatoxin B1 and zearalenone in 96 samples. Working characteristics of the sensor system were estimated. The sensors were shown to be highly-selective towards target mycotoxins. The detection limits for aflatoxin B1 and zearalenone detection comprised 20 ng mL-1 and 1 µg mL-1, respectively. The possibility to detect the aflatoxin B1 and zearalenone in contaminated food samples was shown.
Financial support from National Academy of Sciences of Ukraine and Ministry of Education and Science of Ukraine is gratefully acknowledged.