title: Rapid immunoenzyme assay of aflatoxin B1 using magnetic nanoparticles.
abstract: The main limitations of microplate-based enzyme immunoassays are the prolonged incubations necessary to facilitate heterogeneous interactions, the complex matrix and poorly soluble antigens, and the significant sample dilutions often required because of the presence of organic extractants. This study presents the use of antibody immobilization on the surface of magnetic particles to overcome these limitations in the detection of the mycotoxin, aflatoxin B1. Features of the proposed system are a high degree of nanoparticle dispersion and methodologically simple immobilization of the antibodies by adsorption. Reactions between the immobilized antibodies with native and labeled antigens are conducted in solution, thereby reducing the interaction period to 5 min without impairing the analytical outcome. Adsorption of immunoglobulins on the surface of magnetic nanoparticles increases their stability in aqueous-organic media, thus minimizing the degree of sample dilution required. Testing barley and maize extracts demonstrated a limit of aflatoxin B1 detection equal to 20 pg/mL and total assay duration of 20 min. Using this method, only the 3-fold dilution of the initial methanol/water (60/40) extraction mixture in the microplate wells is necessary. The proposed pseudo-homogeneous approach could be applied toward immunodetection of a wide range of compounds.
authors.affiliation: Bach Institute of Biochemistry of the Russian Academy of Sciences, Leninsky Prospect 33, Moscow 119071, Russia. urusov.alexandr@gmail.com.
authors.forename: Alexandr E
authors.initials: AE
authors.lastname: Urusov
authors.affiliation: Bach Institute of Biochemistry of the Russian Academy of Sciences, Leninsky Prospect 33, Moscow 119071, Russia. alina.petrakova@gmail.com.
authors.forename: Alina V
authors.initials: AV
authors.lastname: Petrakova
authors.affiliation: IL Test-Pushchino Ltd., Gruzovaya Street 1g, Pushchino 142290, Moscow Region, Russia. maxin@test-p.ru.
authors.forename: Maxim V
authors.initials: MV
authors.lastname: Vozniak
authors.affiliation: Bach Institute of Biochemistry of the Russian Academy of Sciences, Leninsky Prospect 33, Moscow 119071, Russia. zherdev@inbi.ras.ru.
authors.forename: Anatoly V
authors.initials: AV
authors.lastname: Zherdev
authors.affiliation: Bach Institute of Biochemistry of the Russian Academy of Sciences, Leninsky Prospect 33, Moscow 119071, Russia. dzantiev@inbi.ras.ru.
authors.forename: Boris B
authors.initials: BB
authors.lastname: Dzantiev
mesh_terms: D016604:Aflatoxin B1 / Q000032:analysis*; D004797:Enzyme-Linked Immunosorbent Assay / Q000295:instrumentation*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005504:Food Analysis / Q000295:instrumentation*; D005506:Food Contamination / Q000032:analysis*; D018189:Immunomagnetic Separation / Q000295:instrumentation*; D058185:Magnetite Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D058185:Magnetite Nanoparticles; D016604:Aflatoxin B1