Immunoaffinity chromatography, coupled

D.W. Roberts, M.I. Churchwell, F.A. Beland, J.-L. Fang, D.R. Doerge, Quantitative analysis of etheno-2 -deoxycytidine DNA adducts using on-line immunoaffinity chromatography coupled with LC-ESI-MS—MS detection. Anal. Chem., 73 (2001) 303. 

Affinity-purified antibodies are isolated from antisera by immunoaffinity chromatography using antigens coupled to agarose beads. 

Fazekas, B. and Tar, A., Determination of zearalenone content in cereals and feedstuff s by immunoaffinity column coupled with liquid chromatography, J. AO AC Int., 84, 1453, 2001. 

Immunoaffinity chromatography cleanup has also been applied as an ideal and reliable strategy for residue analysis. Immunoaffinity columns prepared by coupling the antibodies to a cyanogen bromide-activated support were used to analyze avermectin BI residues in cattle tissues (359) and ivermectin in sheep serum (376). An immunoaffinity column prepared by an alternative activation/ coupling procedure with carbonyl diimidazole was also employed to analyze ivermectin residues in swine liver (361) since the earlier-reported methods did not work well in the analysis of this matrix. This recent work demonstrated the high specificity of tire antibody-mediated cleanup, but also showed that the immunoaffinity procedures could not always or completely eliminate matrix interference of samples. Therefore, application of additional cleanup steps before or after these procedures is often inevitable. 

MW Trucksess, ME Stack, S Nesheim, SW Page, RH Albert, TJ Hansen, KF Donahue. Immunoaffinity column coupled with solution fluorometry or liquid chromatography post-column derivati-... 

Multi-immunoaffinity chromatography columns were prepared by the coupling of monoclonal antibodies against AMP to activated sepharose. Both sensitivity and specificity were tested for the most commonly used penicillins (AMP, AMO, PenG, OXA, CLO, DICL). Recoveries ranging from 67% to 100% were obtained from phosphate buffer solutions, and it was assumed... 

G. S. Rule, A. V. Mordehai and J. Henion, Determination of carbofuran by on-line immunoaffinity chromatography with coupled-column liquid chromatography/mass spectrometry , Anal. Chem. 66 230-235 (1994). 

J. Cai and J. Henion, Quantitative multi-residue determination of /3-agonists in bovine urine using on-line immunoaffinity extraction-coupled column packed capillary liquid chromatography-tandem mass spectrometry , 7. Chromatogr. 691 357-370 (1997). 

As an alternative, immunoaffinity procedures have been developed to selectively extract PAHs from environmental samples. Thomas and Li62 demonstrated the greater efficiency of immunoaffinity methods in comparison with conventional extraction procedures. Bouzige et al.48 prepared an immunosorbent for use in an on-line analytical procedure, followed by liquid chromatography coupled to fluorescence detection, to monitor surface water samples. The sensitivity of the fluorescence detection in combination with the selectivity of the immunosorbent (IS) extraction enabled PAH compounds to be detected at levels between 2 and 10 ng I. 

Cai, J., and Henion, J. (1996) On line immunoaffinity extraction coupled column capillary liquid chromatography/tandem mass spectrometry trace analysis of LSD analogs and metabolites in human urine. Analytical Chemistry, 68, 72 78. 

The first publication that reported the use of LC—MS for quantification of IsoPs in urine used reversed-phase LC coupled with ESI/MS. The method used only 1 mL urine and the clean-up procedure using solid phase extraction (SPE) columns gave quantitative recovery of the IsoP. The chromatographic runs and SPE purification methods are short, and this results in a very easy and user-friendly procedure (Li et al., 1999). A comprehensive review by Tsikas et al. describes sample preparation techniques and compares GC—MS methods with the most recent LC—MS/MS methods (Tsikas et al., 2003). The focus is primarily on 8-f5o-PGF2ci and highlights the difficulty to detect only one IsoP isomer without immunoaffinity chromatography preparation. The large concentration differences for the various IsoP classes in urine are also addressed. 

Holtzapple, C.K. Buckley, S.A. Stanker, L.H. Determination of four fluoroquinolones in milk by on-line immunoaffinity capture coupled with reversed-phase liquid chromatography. J. AOAC Int. 1999, 82 (3), 607. 

Trucksess, M. W., Stack, M. E., Nesheim, S., Page, S. W., Albert, R., Hansen, T. J., and Donahue, K. F. 1991. Immunoaffinity column coupled with solution fluorometry or liquid chromatography postcolumn derivatization for determination of aflatoxins in corn, peanuts and peanut butter Collaborative study. J. Assoc. Offi. Anal. Chem. 74 81-88. 

In the present context, immunoaffinity chromatography and application of the principle to SPE are more important than IMAC. A comprehensive review (Delaunay-Bertoncini 2004) describes the principles of the immunoaffinity SPE approach for pharmaceutical and biomedical analysis, including its coupling with HPLC and LC/MS as well as examples of other apphcations, e.g., to environmental analysis. An immunoaffinity sorbent contains antibodies that are specific to the target analytes and are immobihzed on a sohd support. An excellent free-access source for detailed information on ah aspects of modern biology (Kimball 2006) includes informative descriptions of antibodies, particularly monoclonal antibodies (see below). 

Figure 3 Schemes for coupling immunoaffinity chromatography with other HPLC separation steps. Symbols as s in Fig. 2. ...

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