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Oklestkova J, Tarkowská D, Eyer L, Elbert T, Marek A, Smržová Z, Novák O, Fránek M, Zhabinskii VN, Strnad M. Immunoaffinity chromatography combined with tandem mass spectrometry: A new tool for the selective capture and analysis of brassinosteroid plant hormones. Talanta 2017; 170:432-440. [PMID: 28501193 DOI: 10.1016/j.talanta.2017.04.044] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Revised: 04/12/2017] [Accepted: 04/17/2017] [Indexed: 12/24/2022]
Abstract
Brassinosteroids (BRs) are plant-specific steroid hormones that play essential roles in the regulation of many important physiological processes in plant life. Their extremely low concentrations (~pmoles/g FW) in plant tissue and huge differences in polarity of individual members within the BR family hamper their detection and quantification. To address this problem, an immunoaffinity sorbent with broad specificity and high capacity for different BR metabolites containing a monoclonal antibody (mAb) against a BR spacer (20S)-2α,3α-dihydroxy-7-oxa-7α-homo-5α-pregnane-6-one-20 carboxylic acid (BR4812) was used for the rapid and highly selective isolation of endogenous BRs containing a 2α,3α-diol in ring A from minute plant samples. This enrichment procedure was successfully applied as a sample preparation method prior to quantitative analysis of BRs in real plant tissues by ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). Use of immunoaffinity chromatography (IAC) increased the sensitivity of the UHPLC-MS/MS analysis owing to improvements in the BR signal-to-noise ratio (S/N) and matrix factor (MF). Although MF values of BRs analyzed in classical samples ranged from 8.9% to 47.4%, MF values for the IAC purified samples reached 44.5-96.6%. Thus, the developed IAC-UHPLC-MS/MS approach was shown to be a simple, robust, effective and extremely fast procedure requiring minute amounts of plant samples suitable for the quantitative profiling of many BR metabolites, helping to overcome the major problems associated with their determination in very complex plant matrices.
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Affiliation(s)
- Jana Oklestkova
- Laboratory of Growth Regulators, Centre of the Region Haná for Biotechnological and Agricultural Research, Institute of Experimental Botany, The Czech Academy of Sciences & Faculty of Science, Palacký University, Šlechtitelů 27, CZ-783 71 Olomouc, Czech Republic.
| | - Danuše Tarkowská
- Laboratory of Growth Regulators, Centre of the Region Haná for Biotechnological and Agricultural Research, Institute of Experimental Botany, The Czech Academy of Sciences & Faculty of Science, Palacký University, Šlechtitelů 27, CZ-783 71 Olomouc, Czech Republic.
| | - Luděk Eyer
- Veterinary Research Institute, Hudcova 70, CZ-621 00 Brno, Czech Republic.
| | - Tomáš Elbert
- Institute of Organic Chemistry and Biochemistry, The Czech Academy of Sciences, Flemingovo nám. 2, CZ-166 10 Prague 6, Czech Republic.
| | - Aleš Marek
- Institute of Organic Chemistry and Biochemistry, The Czech Academy of Sciences, Flemingovo nám. 2, CZ-166 10 Prague 6, Czech Republic.
| | - Zora Smržová
- Veterinary Research Institute, Hudcova 70, CZ-621 00 Brno, Czech Republic.
| | - Ondřej Novák
- Laboratory of Growth Regulators, Centre of the Region Haná for Biotechnological and Agricultural Research, Institute of Experimental Botany, The Czech Academy of Sciences & Faculty of Science, Palacký University, Šlechtitelů 27, CZ-783 71 Olomouc, Czech Republic.
| | - Milan Fránek
- Veterinary Research Institute, Hudcova 70, CZ-621 00 Brno, Czech Republic.
| | - Vladimir N Zhabinskii
- Institute of Bioorganic Chemistry, National Academy of Sciences of Belarus, Kuprevich Str., 5/2, 220141 Minsk, Belarus.
| | - Miroslav Strnad
- Laboratory of Growth Regulators, Centre of the Region Haná for Biotechnological and Agricultural Research, Institute of Experimental Botany, The Czech Academy of Sciences & Faculty of Science, Palacký University, Šlechtitelů 27, CZ-783 71 Olomouc, Czech Republic.
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Hauserová E, Swaczynová J, Dolezal K, Lenobel R, Popa I, Hajdúch M, Vydra D, Fuksová K, Strnad M. Batch immunoextraction method for efficient purification of aromatic cytokinins. J Chromatogr A 2005; 1100:116-25. [PMID: 16191431 DOI: 10.1016/j.chroma.2005.09.020] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2005] [Revised: 09/08/2005] [Accepted: 09/09/2005] [Indexed: 11/29/2022]
Abstract
A range of benzylaminopurines naturally occur in plants and exhibit high biological activity. Others have been synthesized, such as 6-(2-hydroxy-3-methoxybenzylamino)purine riboside (2OH3MeOBAPR), which has shown interesting anti-cancer activity under in vitro conditions. In order to study the biological activity of this interesting compound in more detail, a rapid and highly efficient method for its purification from complex samples (e.g. blood and plant extracts) is needed. Therefore, we prepared monoclonal antibodies against 2OH3MeOBAPR. The antibody had undetectable cross-reactivity with all natural isoprenoid cytokinins, but relatively high cross-reactivity with aromatic cytokinins as well as some synthetic di- and tri-substituted 6-benzylaminopurines and the corresponding ribosides. The antibody also showed strong responses and specificity in enzyme-linked immunoassays (ELISAs). In addition, it was used to prepare, for the first time, an immunoaffinity sorbent with high specificity and capacity for aromatic cytokinins. A batch immunoextraction method was then developed and optimized for the purification of 2OH3MeOBAPR from murine blood samples. The high efficacy and simplicity of this method (in off-line combination with HPLC-MS) for the isolation of target analytes from biological material is demonstrated in this study.
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Affiliation(s)
- Eva Hauserová
- Laboratory of Growth Regulators, Palacký University and Institute of Experimental Botany ASCR, Olomouc, Czech Republic
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Shen J, Qian C, Jiang H, Yang H. Development of an enzyme-linked immunosorbent assay for the determination of maduramicin in broiler chicken tissues. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2001; 49:2697-2701. [PMID: 11409953 DOI: 10.1021/jf001520g] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Maduramicin is one of the most widely used coccidiostats in the world. A rapid and accurate analytical method for this drug should provide producers and users with an effective management tool. The current chromatographic methods are sensitive but labor-intensive. This paper reports the development of an enzyme-linked immunosorbent assay (ELISA) based on an immunoaffinity chromatography cleanup procedure for the analysis of maduramicin in broiler chicken tissues (including muscle, liver, and fat). Recoveries from fortified tissue homogenates at levels of 30.0-120.0 microg kg(-)(1) ranged from 76.4 to 107.5% with coefficients of variation of 3.8-16.4%. The limits of detection were 1.0 ng g(-)(1) in muscle, 2.8 ng g(-)(1) in liver, and 1.5 ng g(-)(1) in fat. The ELISA results from the analysis of incurred residue in tissue samples showed the cleanup procedure is viable.
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Affiliation(s)
- J Shen
- College of Veterinary Medicine, China Agricultural University, Beijing 100094, People's Republic of China.
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Delaunay-Bertoncini N, Pichon V, Hennion MC. Comparison of immunoextraction sorbents prepared from monoclonal and polyclonal anti-isoproturon antibodies and optimization of the appropriate monoclonal antibody-based sorbent for environmental and biological applications. Chromatographia 2001. [DOI: 10.1007/bf02490332] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Kong DL, Schuett W, Boeden HF, Kunkel S, Holtz M, Matic G, Yamada R, Yu YT, Klinkmann H. Development of a DNA immunoadsorbent: coupling DNA on sepharose 4FF by an efficient activation method. Artif Organs 2000; 24:845-51. [PMID: 11119070 DOI: 10.1046/j.1525-1594.2000.06618.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
To remove anti-DNA antibodies from a patient's plasma with systemic lupus erythematosus (SLE), a DNA immunoadsorbent was developed by covalently coupling calf thymus DNA on activated Sepharose 4FF. Sepharose 4FF was activated with 5-norbornene-2,3-dicarboximido carbonochloridate (Cl-CO-ONB), which was proven to be a very effective method for preparation of affinity chromatographic adsorbents. The activation was carried out in dry acetone using 4-(dimethylamine)pyridine (DMAP) and triethylamine (TEA) as catalysts at 4 degrees C or at room temperature. The coupling of DNA to the activated support was investigated as a function of pH, temperature, time, concentration of DNA, and activation level. It was found that the pH for optimal coupling is 3.0, and the amount of coupled DNA increases with an increase either in the concentration of DNA or the activation level. The maximum amount of coupled DNA could reach 1.0 mg DNA/ml support. The incubation of 5 to 20 ml of SLE plasma with 1.0 ml of adsorbent resulted in an 80 to 90% decline in the anti-DNA antibody level. Nonspecific adsorption for normal IgG and total protein is less than 15%.
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Affiliation(s)
- D L Kong
- R&D Center of Bioengineering, Rostock, Germany
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Delaunay N, Pichon V, Hennion MC. Immunoaffinity solid-phase extraction for the trace-analysis of low-molecular-mass analytes in complex sample matrices. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL SCIENCES AND APPLICATIONS 2000; 745:15-37. [PMID: 10997702 DOI: 10.1016/s0378-4347(00)00116-x] [Citation(s) in RCA: 113] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Immunoaffinity solid-phase extraction (SPE) sorbents, so-called immunosorbents (ISs), are based upon molecular recognition using antibodies. Thanks to the high affinity and high selectivity of the antigen-antibody interaction, they allow a high degree of molecular selectivity and have shown to be a unique tool in the sample preparation area these last few years. Extraction and clean-up of complex biological and environmental aqueous samples are achieved in the same step and from large volumes when required. Their application to extracts from solid matrixes is solvent-free and more simple than any other clean-up procedure. Single analytes can be targeted, but since an antibody can also bind one or more analytes having structure similar to the one used for its preparation, ISs have been developed for targeting a single analyte and its metabolites. The cross-reactivity was also exploited for developing ISs that could selectively extract a whole class of structurally related compounds. This review describes the current technology used for the synthesis of the ISs, their properties and their field of application. The different parameters governing the antigen-antibody interactions and the solid-phase extraction process are discussed. Emphasis is given to the optimisation of the SPE sequence, especially to the desorption and regeneration steps. The importance of the capacity and its relationship with the analytes recovery and breakthrough volumes is highlighted for class-specific ISs. Multi-class-selective ISs are also presented. Validation studies are reviewed using various certified reference materials. Relevant examples, involving combination with chromatography in both off-line and on-line mode, illustrate the high selectivity provided in various complex matrixes. Miniaturisation is also described, since it allows high throughput of samples.
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Affiliation(s)
- N Delaunay
- Laboratoire Environnement et Chimie Analytique CNRS 657, Ecole Supérieure de Physique et de Chimie Industrielles, Paris, France
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Beale MH. Immunological methods in plant hormone research. BIOCHEMISTRY AND MOLECULAR BIOLOGY OF PLANT HORMONES 1999. [DOI: 10.1016/s0167-7306(08)60483-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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Hage DS. Survey of recent advances in analytical applications of immunoaffinity chromatography. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL SCIENCES AND APPLICATIONS 1998; 715:3-28. [PMID: 9792495 DOI: 10.1016/s0378-4347(97)00621-x] [Citation(s) in RCA: 134] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Methods that use immunoaffinity chromatography (IAC) for sample preparation or detection are becoming increasingly popular as tools in the analysis of biological and nonbiological compounds. This paper presents an overview of immunoaffinity chromatography and examines some recent developments of this technique in analytical applications. The emphasis is placed on HPLC-based IAC methods or those that combine IAC with other instrumental techniques; however, novel approaches that employ low-performance IAC columns for chemical quantitation are also considered. Particular applications that are examined include (1) the use of IAC in the direct detection of analytes, (2) the extraction of samples by IAC prior to on- or off-line detection by other methods, (3) the use of IAC in chromatographic-based immunoassays, and (4) the development of postcolumn reactors based on IAC for the detection of analytes as they elute from other types of chromatographic columns. The advantages and limitations for each approach are considered. In addition, a summary is provided of reports in the literature that have used IAC for these various formats.
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Affiliation(s)
- D S Hage
- Department of Chemistry, University of Nebraska-Lincoln 68588-0304, USA
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Vankova R, Gaudinová A, Süssenbeková H, Dobrev P, Strnad M, Holík J, Lenfeld J. Comparison of oriented and random antibody immobilization in immunoaffinity chromatography of cytokinins. J Chromatogr A 1998; 811:77-84. [PMID: 9691302 DOI: 10.1016/s0021-9673(98)00210-6] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Immunosorbents for the plant hormones cytokinins prepared by random antibody immobilization (to Affi-Gel 10) and by oriented approach via oxidized carbohydrate moieties on the Fc region (to Affi-Gel Hz or hydrazide derivative of Perloza MT 200) have been compared. Both approaches yielded immunosorbents with high dynamic capacity (ca. 5-10 nmol ml gel-1). Oriented antibody immobilization did not exhibit crucial effects in the case of low-molecular-mass cytokinins. Antibodies immobilized via a spacer to Affi-Gel 10 have probably enough conformational freedom to enable good accessibility to cytokinins. The sorbents were used in analysis of endogenous cytokinins in maize seeds. In phosphatase treated samples trans-zeatin and its riboside were predominant.
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Affiliation(s)
- R Vankova
- Institute of Experimental Botany, Academy of Sciences of the Czech Republic, Prague, Czech Republic
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11
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Combining immunoassays with chromatographic and electrophoretic separation techniques ? a review. Mikrochim Acta 1998. [DOI: 10.1007/bf01246844] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Hormonal Regulation of Seed Development. ADVANCES IN CELLULAR AND MOLECULAR BIOLOGY OF PLANTS 1997. [DOI: 10.1007/978-94-015-8909-3_4] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
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Nicander B, Ståhl U, Björkman PO, Tillberg E. Immunoaffinity co-purification of cytokinins and analysis by high-performance liquid chromatography with ultraviolet-spectrum detection. PLANTA 1993; 189:312-20. [PMID: 24178487 DOI: 10.1007/bf00194427] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 10/10/1992] [Indexed: 05/27/2023]
Abstract
A rapid methodology for the simultaneous analysis of a large number of cytokinins is presented. The cross-reactivity of a mixture of polyclonal antibodies against zeatin riboside and isopentenyladenosine was exploited in a protocol that can be used for immunoaffinity purification of 23 additional cytokinins. Ligands include the cytokinin bases zeatin, dihydrozeatin, isopentenyladenine, benzyl-adenine and kinetin, and their corresponding nucleoside, nucleoside-5'-monophosphate, and 9-glucoside derivatives, as well as cis-zeatin, cis-zeatin riboside, the 2-methylthiol derivatives of isopentenyladenosine and zeatin riboside, and benzyl-adenine-3-glucoside. Mixtures of cytokinins could be retained with high recoveries of all the components. Immunoaffinity purification of extracts of Arabidopsis thaliana (L.) Heynh. and Solarium tuberosum L. gave fractions clean enough, as verified by gas chromatographymass spectrometry (GC-MS), to allow analysis of endogenous cytokinins using a single high-performance liquid chromatography (HPLC) step with on-line UV-spectrum detection. The detection limit was 4-6 pmol. The procedure described forms a routine assaying technique that is faster and simpler, yet yields better qualitative and quantitative information than the commonly used procedure of immunoassaying of HPLC fractions.
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Affiliation(s)
- B Nicander
- Department of Plant Physiology, Swedish University of Agricultural Science, P.O. Box 7047, S-75007, Uppsala, Sweden
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Irth H, Oosterkamp A, van der Welle W, Tjaden U, van der Greef J. On-line immunochemical detection in liquid chromatography using fluorescein-labelled antibodies. J Chromatogr A 1993. [DOI: 10.1016/0021-9673(93)83138-i] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Yarmush ML, Weiss AM, Antonsen KP, Odde DJ, Yarmush DM. Immunoaffinity purification: Basic principles and operational considerations. Biotechnol Adv 1992; 10:413-46. [PMID: 14546282 DOI: 10.1016/0734-9750(92)90303-q] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Immunoaffinity purification has become an important technique in biotechnology. In this review the basic principles of immunoaffinity separations are described with respect to the stages of operation and potential application. The most commonly used support materials, activation procedures, and coupling chemistries are compared to one another for suitability in various applications. Individual operational steps for fixed bed immunoadsorbents including loading, washing, elution and regeneration are described in terms of both theory and practice. Factors influencing adsorbent stability are identified, and alternative operation and configuration strategies are discussed in light of their application to immunoaffinity systems.
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Affiliation(s)
- M L Yarmush
- Department of Chemical and Biochemical Engineering and the Center for Advanced Biotechnology and Medicine, Rutgers University, Piscataway, NJ 08855, USA
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Abstract
To overcome the adverse consequences of antibody immobilization (impairment of the antigen-binding parameters) the interaction of a number of antigens with both soluble and covalently immobilized antibodies in the presence of water-soluble polymers has been investigated. Incorporation of some water-soluble polymers (Ficoll, Dextran) into the assay mixture was shown to substantially increase the antigen-binding capacity of both soluble and immobilized antibodies. The use of dextran T70 enhanced the sensitivity of competitive radioimmunoassays for CEA and beta 2-microglobulin 3-4-fold. This procedure may be also applied to shorten the incubation period when performing an assay.
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Affiliation(s)
- V M Guzov
- Institute of Bioorganic Chemistry, Byelorussian Academy of Sciences, Minsk, U.S.S.R
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Wimalasena RL, Wilson GS. Factors affecting the specific activity of immobilized antibodies and their biologically active fragments. JOURNAL OF CHROMATOGRAPHY 1991; 572:85-102. [PMID: 1818078 DOI: 10.1016/0378-4347(91)80475-r] [Citation(s) in RCA: 59] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Factors affecting the specific activity of immobilized antibodies and their biologically active fragments were studied with goat anti-mouse and goat anti-human immunoglobulin G. Antibodies were immobilized on HW 65 polymeric support matrix activated with carbonyldiimidazole, hydrazide and iodoacetic acid. The most significant factors influencing the specific activity of stochastic coupling of antibodies are multi-site attachment, multiple orientations and steric hindrance imposed by crowding of antibody and the size of the antigen. In oriented immobilization the specific activity is affected only by steric hindrance. The specific activity of immunosorbents prepared by immobilization of F(ab') fragments can be improved to almost 100% by limiting the amount of protein immobilization and the size of the antigen. The present study shows the protocols for optimizing immobilized antibody performance.
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Affiliation(s)
- R L Wimalasena
- Department of Chemistry, University of Kansas, Lawrence 66045
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Meeley MP, Towle AC, Ernsberger P, Char LK, McCauley PM, Reis DJ. Clonidine-specific antisera recognize an endogenous clonidine-displacing substance in brain. Hypertension 1989; 13:341-51. [PMID: 2925235 DOI: 10.1161/01.hyp.13.4.341] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
An endogenous substance in brain, clonidine-displacing substance, binds to the same receptor populations as clonidine and is biologically active. Since receptor binding sites can be modeled by using specific antiligand antibodies, we tested the hypothesis that polyclonal antibodies raised in rat and rabbit against the clonidine analog p-aminoclonidine coupled to hemocyanin would recognize compounds structurally related to clonidine, including clonidine-displacing substance. Binding to anti-p-aminoclonidine antibodies was examined by using a competitive radioimmunoassay with tritiated p-aminoclonidine as the radioligand. Central vasodepressor agents that, like clonidine, are known to bind with high affinity to both imidazole sites and alpha 2-adrenergic receptors in brain inhibited radioligand binding to anti-p-aminoclonidine antibodies. All of these agents contain imidazol(in)e and phenyl ring moieties as part of their chemical structures (e.g., oxymetazoline); a number of other compounds without one or both of these rings failed to cross-react with the antisera. Clonidine-displacing substance, partially purified from bovine brain, also inhibited specific radioligand binding to anti-p-aminoclonidine antibodies. The inhibition was dose dependent and high affinity (IC50, 4 Units). The endogenous substance had no effect on the apparent affinity of the antibodies for the radioligand, but blocked a specific number of binding sites. Immunoprecipitation experiments showed that authentic clonidine-displacing substance, that which displaces tritiated p-aminoclonidine binding to membrane receptors, is recognized by anti-p-aminoclonidine antibodies. We conclude that a unique subset of structural determinants required for ligand interaction with both imidazole and alpha 2-adrenergic receptors is critical for binding to anti-p-aminoclonidine antibodies, and that since clonidine-displacing substance is recognized by highly clonidine-specific antisera, it may also contain these determinants within its structure, namely the imidazol(in)e and phenyl ring systems.
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Affiliation(s)
- M P Meeley
- Division of Neurobiology, Cornell University Medical College, New York, New York 10021
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Farjam A, de Jong GJ, Frei RW, Brinkman UA, Haasnoot W, Hamers AR, Schilt R, Huf FA. Immunoaffinity pre-column for selective on-line sample pre-treatment in high-performance liquid chromatography determination of 19-nortestosterone. J Chromatogr A 1988; 452:419-33. [PMID: 3072346 DOI: 10.1016/s0021-9673(01)81465-5] [Citation(s) in RCA: 70] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
A liquid chromatographic column-switching system for automated sample pretreatment and determination of the anabolic hormone beta-19-nortestosterone (beta-19-NT) and its metabolite alpha-19-nortestosterone (19-norepitestosterone) in calf urine is described. The system consists of an immunoaffinity pre-column (immuno pre-column) packed with Sepharose-immobilized polyclonal antibodies against beta-19-NT, a second pre-column packed with C18 bonded silica and an analytical C18 column. Urine (25 ml) is directly loaded on the immuno pre-column, where the analytes of interest are trapped by the immobilized antibodies. Next the analytes are desorbed selectively with a solution containing an excess of the cross-reacting steroid hormone norgestrel and transferred, via the second pre-column, to the analytical column. The recovery of beta-19-NT in spiked urine samples was over 95%. The detection limit was 50 ng/l for a 25-ml urine injection. The system showed no loss of analytical performance over a 6-month period, during which about 100 samples were analysed with the same immuno pre-column. The general applicability of this sample pretreatment method is discussed.
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Affiliation(s)
- A Farjam
- Department of Analytical Chemistry, Free University, Amsterdam, The Netherlands
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van de Water C, Haagsma N. Determination of chloramphenicol in swine muscle tissue using a monoclonal antibody-mediated clean-up procedure. J Chromatogr A 1987; 411:415-21. [PMID: 3443630 DOI: 10.1016/s0021-9673(00)93993-1] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
A rapid and specific clean-up procedure based on immunoaffinity chromatography for the high-performance liquid chromatographic determination of chloramphenicol (CAP) in swine muscle tissue at the 10 micrograms kg-1 level is described. For preparation of the columns, monoclonal antibodies against CAP were coupled to cyanogen bromide-activated Sepharose. After immunosorption of CAP from the aqueous meat extract, CAP was eluted with methanol. Mean recoveries from spiked swine muscle tissue were 70 +/- 6% (10-50 micrograms kg-1 spiking levels). The loss of CAP can be completely attributed to the extraction; no loss was observed during the antibody-mediated clean-up.
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Affiliation(s)
- C van de Water
- Faculty of Veterinary Medicine, Department of the Science of Food of Animal Origin, University of Utrecht, The Netherlands
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