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Sergei A. Eremin - One of the best experts on this subject based on the ideXlab platform.

  • development of Fluorescence Polarization Immunoassay for imidacloprid in environmental and agricultural samples
    Frontiers in Chemistry, 2020
    Co-Authors: Liangliang Zhou, Sergei A. Eremin, Xiude Hua, Jiachuan Yang, Zhexuan Tao, Minghua Wang
    Abstract:

    A Fluorescence Polarization Immunoassay (FPIA) for the determination of imidacloprid (IMI) was developed with advantages of simple operation and short assays time. The haptens of IMI, acetamiprid (ACE) and thiamethoxam (THI) were conjugated with fluorescein isothiocyanate ethylenediamine (EDF) and 4’-Aminomethyl fluorescein (AMF) respectively to prepare six Fluorescence tracers. The conjugation of IMI hapten and EDF (IMI-EDF) was selected to develop the FPIA due to the largest fluorescent Polarization value increase in the presence of anti-IMI monoclonal antibody. Under the optimum condition, the limit of detection, 50% inhibition concentration and detection range of the FPIA were 1.7, 4.8 and 1.7-16.3 µg/L, respectively. The cross-reactivities (CRs) with the analogues of IMI were negligible except for imidaclothiz with CR of 79.13%. The average recovery of spiked paddy water, corn and cucumber samples were 82.4%-118.5% with the RSDs of 7.0%-15.9%, which indicated the FPIA had good accuracy. Thus, the developed FPIA was a potential tool for the rapid and accurate determination of IMI in agricultural and environmental samples.

  • Fluorescence Polarization Immunoassay for the determination of diclofenac in wastewater
    Analytical and Bioanalytical Chemistry, 2020
    Co-Authors: Anna Raysyan, Sergei A. Eremin, Robin Moerer, Bianca Coesfeld, Rudolf J. Schneider
    Abstract:

    Pharmacologically active compounds are often detected in wastewater and surface waters. The nonsteroidal anti-inflammatory drug diclofenac (DCF) was included in the European watch list of substances that requires its environmental monitoring in the member states. DCF may harmfully influence the ecosystem already at concentrations ≤ 1 μg L^−1. The fast and easy quantification of DCF is becoming a subject of global importance. Fluorescence Polarization Immunoassay (FPIA) is a homogeneous mix-and-read method which does not require the immobilization of reagents. FPIA can be performed in one phase within 20–30 min, making it possible to analyse wastewater without any complicated pre-treatment. In this study, new tracer molecules with different structures, linking fluorophores to derivatives of the analyte, were synthesized, three homologous tracers based on DCF, two including a C_6 spacer, and one heterologous tracer derived from 5-hydroxy-DCF. The tracer molecules were thoroughly assessed for performance. Regarding sensitivity of the FPIA, the lowest limit of detection reached was 2.0 μg L^−1 with a working range up to 870 μg L^−1. The method was validated for real wastewater samples against LC-MS/MS as reference method with good agreement of both methods. Graphical abstract

  • Fluorescence Polarization Immunoassay of colchicine
    Journal of pharmaceutical and biomedical analysis, 2018
    Co-Authors: Elena A. Zvereva, Ramadan A Abuknesha, Sergei A. Eremin, Anatoly V Zherdev, Andrei A Formanovsky, Boris B Dzantiev
    Abstract:

    Abstract In this study, a Fluorescence Polarization Immunoassay (FPIA) technique was developed to determine colchicine (COL), an alkaloid of noxious plants of the order Liliales that is used in a number of medications to treat gout. An optimal combination of the polyclonal antibody and the antigen labelled with fluorescein isothiocyanate (FITC) was selected. Conditions for the competitive interaction of the antigen in the tested samples and its fluorophore conjugate (COL–FITC) with anti-COL antibodies were optimised, and the analytical characteristics of the assay were determined. The developed FPIA was characterised by a detection limit of 1.8 ng/mL and a detectable analyte concentration range of 4.1–74.3 ng/mL. The duration of the analysis was 10 min. The applicability of the developed FPIA for quality control of ready-made drug formulations and for the estimation of COL content in various matrices (urine, milk), with recovery values ranging from 79 to 108%, was demonstrated.

  • Fluorescence Polarization Immunoassay of ractopamine
    Applied Biochemistry and Microbiology, 2016
    Co-Authors: Elena A. Zvereva, N. A. Shpakova, Sergei A. Eremin, Anatoly V Zherdev, Boris B Dzantiev
    Abstract:

    A technique was developed for Fluorescence Polarization Immunoassay (FPIA) of ractopamine, a toxic low molecular weight nonsteroidal growth regulator belonging to the most controlled contaminants of food products of animal origin. The assay is based on the competition between a sample containing ractopamine and ractopamine–fluorophore conjugate for binding to antibodies. The competition is monitored via changes in the degree of Fluorescence Polarization for plane-polarized excitation light, which differs for the free and antibody-bound forms of the conjugate. The optimal assay conditions were established, ensuring a high accuracy and minimal detection limit. The developed assay demonstrated a detection limit of 1 ng/mL and a range of detectable concentrations of 2.3–50 ng/mL, which met the requirements of sanitary control. The duration of the analysis was 10 min. The possible application of the developed FPIA was demonstrated with testing of turkey meat. The speed and simplicity of the proposed assay define its efficiency as a screening tool for safety of foods.

  • Determination of 2,4-dichlorophenoxyacetic acid in cereals by Fluorescence Polarization Immunoassay
    Journal of Analytical Chemistry, 2016
    Co-Authors: A. Yu. Boroduleva, Sergei A. Eremin
    Abstract:

    A Fluorescence Polarization Immunoassay (FPIA) procedure is developed for the determination of 2,4-dichlorophenoxyacetic acid in cereal grains using a Sentry-200 portable device. We synthesized tracers, that is, antigens labeled with fluorescein derivatives, based on two fluorescent compounds and two chlorophenoxyacids. The tracer synthesized from 2,4-dichlorophenoxyacetic acid and 4-aminomethylfluorescein is found to be optimal for the FPIA of 2,4-dichlorophenoxyacetic acid. The limit of detection for 2,4-dichlorophenoxyacetic acid in flour was 40 ng/g; the analytical range is from 80 to 1000 ng/g. The percentage of recovery was 85 ± 7% at the relative standard deviation (RSD) 2–10%.

Boris B Dzantiev - One of the best experts on this subject based on the ideXlab platform.

  • Fluorescence Polarization Immunoassay of colchicine
    Journal of pharmaceutical and biomedical analysis, 2018
    Co-Authors: Elena A. Zvereva, Ramadan A Abuknesha, Sergei A. Eremin, Anatoly V Zherdev, Andrei A Formanovsky, Boris B Dzantiev
    Abstract:

    Abstract In this study, a Fluorescence Polarization Immunoassay (FPIA) technique was developed to determine colchicine (COL), an alkaloid of noxious plants of the order Liliales that is used in a number of medications to treat gout. An optimal combination of the polyclonal antibody and the antigen labelled with fluorescein isothiocyanate (FITC) was selected. Conditions for the competitive interaction of the antigen in the tested samples and its fluorophore conjugate (COL–FITC) with anti-COL antibodies were optimised, and the analytical characteristics of the assay were determined. The developed FPIA was characterised by a detection limit of 1.8 ng/mL and a detectable analyte concentration range of 4.1–74.3 ng/mL. The duration of the analysis was 10 min. The applicability of the developed FPIA for quality control of ready-made drug formulations and for the estimation of COL content in various matrices (urine, milk), with recovery values ranging from 79 to 108%, was demonstrated.

  • Fluorescence Polarization Immunoassay of ractopamine
    Applied Biochemistry and Microbiology, 2016
    Co-Authors: Elena A. Zvereva, N. A. Shpakova, Sergei A. Eremin, Anatoly V Zherdev, Boris B Dzantiev
    Abstract:

    A technique was developed for Fluorescence Polarization Immunoassay (FPIA) of ractopamine, a toxic low molecular weight nonsteroidal growth regulator belonging to the most controlled contaminants of food products of animal origin. The assay is based on the competition between a sample containing ractopamine and ractopamine–fluorophore conjugate for binding to antibodies. The competition is monitored via changes in the degree of Fluorescence Polarization for plane-polarized excitation light, which differs for the free and antibody-bound forms of the conjugate. The optimal assay conditions were established, ensuring a high accuracy and minimal detection limit. The developed assay demonstrated a detection limit of 1 ng/mL and a range of detectable concentrations of 2.3–50 ng/mL, which met the requirements of sanitary control. The duration of the analysis was 10 min. The possible application of the developed FPIA was demonstrated with testing of turkey meat. The speed and simplicity of the proposed assay define its efficiency as a screening tool for safety of foods.

  • production of polyclonal antibodies and development of Fluorescence Polarization Immunoassay for sulfanilamide
    Analytical Letters, 2005
    Co-Authors: Sergei A. Eremin, Anatoly V Zherdev, E.v. Yazynina, Nailya R Murtazina, Dmitri N Ermolenko, Andrey A Martianov, Irina V Michura, Andrei A Formanovsky, Boris B Dzantiev
    Abstract:

    Abstract N‐sulfanil‐4‐aminobutyric acid (SAB), which mimics common parts of the sulfonamides' structure, was synthesized and used to produce antibodies to sulfanilamide. Rabbit polyclonal antibodies have been raised using SAB conjugates with ovalbumin (OVA) or soybean trypsin inhibitor (STI). The immunogen based on SAB‐STI could yield higher affinity anitbodies against sulfanilamide. The same SAB derivative was used for synthesis of a fluorescein‐labeled tracer with fluorescein‐thiocarbamyl ethylendiamine. A Fluorescence Polarization Immunoassay (FPIA) for sulfanilamide was developed. The limits of detection sulfanilamide were 0.07, 0.10, and 0.07 µg mL−1 for water, diluted milk, and precipitated milk samples, respectively. The developed FPIA exhibited sensitivities below the respective maximal residue limits (MRLs) for individual sulfonamides (0.1 µg mL−1). The coefficients of variation of results for milk samples were lower than 5%. Total time for simple sample pretreatment and measurement is about 10 m...

  • Development of a rapid, specific Fluorescence Polarization Immunoassay for the herbicide chlorsulfuron
    Analytica Chimica Acta, 2002
    Co-Authors: Sergei A. Eremin, Anatoly V Zherdev, E.v. Yazynina, I.a Ryabova, Julia Yakovleva, Boris B Dzantiev
    Abstract:

    Abstract A strategy for design of a derivative of chlorsulfuron, which mimics half of the herbicide molecule, was proposed. The 1-[(2-chloro)phenylsulfonyl]monoamidosuccinic acid was synthesized as a derivative of chlorsulfuron for conjugation to carrier proteins. Rabbits were immunized and the resulting polyclonal antibodies were assessed by the Fluorescence Polarization technique. The antibodies were highly specific to chlorsulfuron. Cross-reactivity to the structurally similar sulfonylurea and urea herbicides chlorbromuron, amidosulfuron, chlortoluron, isoproturon, diuron and linuron was less than 0.1%. A rapid Fluorescence Polarization Immunoassay (FPIA) for chlorsulfuron detection in water samples was developed and optimized. The detection limit of chlorsulfuron in 50 μl of sample was 10 ng ml −1 . Total time for the measurement of 10 samples is 7 min. The proposed FPIA is suitable for rapid testing for pesticide contamination where the highest sensitivity is not critical or in combination with pre-concentration techniques.

Agustina Gómez-hens - One of the best experts on this subject based on the ideXlab platform.

  • Long-wavelength Fluorescence Polarization Immunoassay: determination of amikacin on solid surface and gliadins in solution.
    Analytical chemistry, 2007
    Co-Authors: María Lourdes Sánchez-martínez, María Paz Aguilar-caballos, Agustina Gómez-hens
    Abstract:

    The versatility of the Fluorescence Polarization Immunoassay (FPIA) is increased by using two long-wavelength labels, Nile Blue and a ruthenium(II) chelate. The first label has been used to study t...

  • Stopped-flow Fluorescence Polarization Immunoassay.
    Combinatorial chemistry & high throughput screening, 2003
    Co-Authors: Agustina Gómez-hens, M.p. Aguilar-caballos
    Abstract:

    A general survey of the analytical application of kinetic methodology in Fluorescence Polarization Immunoassay (FPIA) is presented. Stopped-flow mixing technique (SF) allows the initial rate of the immunochemical reaction between the tracer and the antibody to be obtained, which is used as the analytical parameter instead of the equilibrium signal used in conventional FPIA. The instrumentation required is described and the features of the analytical methods proposed are compared with those obtained by conventional FPIA. The usefulness of SF-FPIA for routine screening in clinical, environmental and food analysis is discussed.

  • Use of stopped-flow Fluorescence Polarization Immunoassay in drug determinations
    Analytica Chimica Acta, 1993
    Co-Authors: Abaji Gaikwad, Agustina Gómez-hens, Dolores Pérez-bendito
    Abstract:

    Abstract The stopped-flow technique was used jointly with Fluorescence Polarization Immunoassay for the kinetic determination of haptens. Two different types of analytes, namely benzodiazepines and tricyclic antidepressants, were assayed in order to assess the advantages of this novel approach over the conventional equilibrium technique. Kinetic data can be obtained within a few seconds after the reactants have been mixed, which allows ready application of this technique to routine analyses. The within- and between-assay precision data are better and detection limits lower than those afforded by conventional Fluorescence Polarization Immunoassay. The analytical recoveries ranged between 98.6 and 101.5% for nordiazepam in urine and between 97.1 and 102.0% for imipramine in serum. The results for serum and urine samples correlated well with those obtained by using the conventional method.

Rudolf J. Schneider - One of the best experts on this subject based on the ideXlab platform.

  • Fluorescence Polarization Immunoassay for the determination of diclofenac in wastewater
    Analytical and Bioanalytical Chemistry, 2020
    Co-Authors: Anna Raysyan, Sergei A. Eremin, Robin Moerer, Bianca Coesfeld, Rudolf J. Schneider
    Abstract:

    Pharmacologically active compounds are often detected in wastewater and surface waters. The nonsteroidal anti-inflammatory drug diclofenac (DCF) was included in the European watch list of substances that requires its environmental monitoring in the member states. DCF may harmfully influence the ecosystem already at concentrations ≤ 1 μg L^−1. The fast and easy quantification of DCF is becoming a subject of global importance. Fluorescence Polarization Immunoassay (FPIA) is a homogeneous mix-and-read method which does not require the immobilization of reagents. FPIA can be performed in one phase within 20–30 min, making it possible to analyse wastewater without any complicated pre-treatment. In this study, new tracer molecules with different structures, linking fluorophores to derivatives of the analyte, were synthesized, three homologous tracers based on DCF, two including a C_6 spacer, and one heterologous tracer derived from 5-hydroxy-DCF. The tracer molecules were thoroughly assessed for performance. Regarding sensitivity of the FPIA, the lowest limit of detection reached was 2.0 μg L^−1 with a working range up to 870 μg L^−1. The method was validated for real wastewater samples against LC-MS/MS as reference method with good agreement of both methods. Graphical abstract

  • Application of Fluorescence Polarization Immunoassay for determination of carbamazepine in wastewater
    Journal of environmental management, 2017
    Co-Authors: Lidia Oberleitner, Ursula Dahmen-levison, Leif-alexander Garbe, Rudolf J. Schneider
    Abstract:

    Carbamazepine is an antiepileptic drug that can be used as a marker for the cleaning efficiency of wastewater treatment plants. Here, we present the optimization of a fast and easy on-site measurement system based on Fluorescence Polarization Immunoassay and the successful application to wastewater. A new monoclonal highly specific anti-carbamazepine antibody was applied. The automated assay procedure takes 16 min and does not require sample preparation besides filtration. The recovery rates for carbamazepine in wastewater samples were between 60.8 and 104% with good intra- and inter-assay coefficients of variations (less than 15 and 10%, respectively). This automated assay enables for the on-site measurement of carbamazepine in wastewater treatment plants.

Dolores Pérez-bendito - One of the best experts on this subject based on the ideXlab platform.

  • Use of stopped-flow Fluorescence Polarization Immunoassay in drug determinations
    Analytica Chimica Acta, 1993
    Co-Authors: Abaji Gaikwad, Agustina Gómez-hens, Dolores Pérez-bendito
    Abstract:

    Abstract The stopped-flow technique was used jointly with Fluorescence Polarization Immunoassay for the kinetic determination of haptens. Two different types of analytes, namely benzodiazepines and tricyclic antidepressants, were assayed in order to assess the advantages of this novel approach over the conventional equilibrium technique. Kinetic data can be obtained within a few seconds after the reactants have been mixed, which allows ready application of this technique to routine analyses. The within- and between-assay precision data are better and detection limits lower than those afforded by conventional Fluorescence Polarization Immunoassay. The analytical recoveries ranged between 98.6 and 101.5% for nordiazepam in urine and between 97.1 and 102.0% for imipramine in serum. The results for serum and urine samples correlated well with those obtained by using the conventional method.