title: Rapid detection of Aspergillus flavus in rice using biofunctionalized carbon nanotube field effect transistors.
abstract: In the present study, we have used carbon nanotube field effect transistors (FET) that have been functionalized with protein G and IgG to detect Aspergillus flavus in contaminated milled rice. The adsorbed protein G on the carbon nanotubes walls enables the IgG anti-Aspergillus antibodies to be well oriented and therefore to display full antigen binding capacity for fungal antigens. A solution of Tween 20 and gelatine was used as an effective blocking agent to prevent the non-specific binding of the antibodies and other moulds and also to protect the transducer against the interferences present in the rice samples. Our FET devices were able to detect at least 10 μg/g of A. flavus in only 30 min. To evaluate the selectivity of our biosensors, Fusarium oxysporum and Penicillium chrysogenum were tested as potential competing moulds for A. flavus. We have proved that our devices are highly selective tools for detecting mycotoxigenic moulds at low concentrations in real samples.
authors.affiliation: Department of Analytical and Organic Chemistry, Universitat Rovira i Virgili, Marcellí. Domingo, s/n, 43007 Tarragona, Spain.
authors.forename: Raquel A
authors.initials: RA
authors.lastname: Villamizar
authors.forename: Alicia
authors.initials: A
authors.lastname: Maroto
authors.forename: F Xavier
authors.initials: FX
authors.lastname: Rius
mesh_terms: D001231:Aspergillus flavus / Q000737:chemistry* / Q000302:isolation & purification; D015374:Biosensing Techniques / Q000295:instrumentation / Q000379:methods*; D005506:Food Contamination / Q000032:analysis*; D037742:Nanotubes, Carbon / Q000737:chemistry*; D012275:Oryza / Q000382:microbiology*; D014173:Transistors, Electronic
chemical_list: D037742:Nanotubes, Carbon