title: Sensitive immunochemical approaches for quantitative (FPIA) and qualitative (lateral flow tests) determination of gentamicin in milk.
abstract: Three kinds of immunoassays for the determination of gentamicin in milk samples were developed and validated. First, a fast and easily-performed fluorescence polarization immunoassay was used for characterization of the employed polyclonal antibody. The calculated Kaff were (1.9±0.4)×10(9)М(-1) and (6.0±0.2)×10(6)М(-1) for the high- and low-affinity fractions respectively. The assay was characterized with a good sensitivity, the limit of detection being 5μgkg(-1). Two different kinds of detection labels, i.e. colloidal gold (CG) and quantum dots (QDs), were evaluated for use in lateral-flow format with respect to rapid visual on-site testing. The cut-off levels for both qualitative formats were selected based on the maximum level for gentamicin in milk established by the European Commission, 100μgkg(-1), resulting in a 10μgkg(-1) cut-off considering sample dilution. The intra-laboratory validation was performed with sterilized milk samples artificially spiked with gentamicin at concentrations less than, equal to, and greater than the cut-off level. It was shown that milk products could be analyzed without any sample preparation, except for dilution with the buffer solution. The rates of false-positive and false-negative results were below 5% for both labels. The different developed immunoassays were tested towards gentamicin determination in artificially-spiked and naturally contaminated milk samples.
authors.affiliation: Ghent University, Faculty of Pharmaceutical Sciences, Laboratory of Food Analysis, Ottergemsesteenweg 460, 9000 Ghent, Belgium. Electronic address: beloglazovanv@gmail.com.
authors.forename: N V
authors.initials: NV
authors.lastname: Beloglazova
authors.affiliation: OJSC CSRIT Technomash, "Neuronet", 121108 Moscow, Russia.
authors.forename: P S
authors.initials: PS
authors.lastname: Shmelin
authors.affiliation: M.V. Lomonosov Moscow State University, Faculty of Chemistry, Department of Chemical Enzymology, Leninsky Gory 1, 119991 Moscow, Russia; A.N. Bach Institute of Biochemistry of the Russian Academy of Sciences, Leninsky prospect 33, 119071 Moscow, Russia.
authors.forename: S A
authors.initials: SA
authors.lastname: Eremin
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000032:analysis* / Q000737:chemistry / Q000276:immunology; D000906:Antibodies / Q000276:immunology; D016231:Fluorescence Polarization Immunoassay; D005506:Food Contamination / Q000032:analysis; D005839:Gentamicins / Q000032:analysis* / Q000737:chemistry / Q000276:immunology; D006046:Gold / Q000737:chemistry; D053768:Metal Nanoparticles / Q000737:chemistry; D008892:Milk / Q000737:chemistry*; D010047:Ovalbumin / Q000737:chemistry; D045663:Quantum Dots / Q000737:chemistry
chemical_list: D000900:Anti-Bacterial Agents; D000906:Antibodies; D005839:Gentamicins; D006046:Gold; D010047:Ovalbumin
keywords: Colloidal gold; Fluorescence polarization immunoassay; Gentamicin; Lateral-flow test; Milk; Quantum dots