Immunoextraction

N. Delaunay, V. Pichon and M.C. Hennion, Experimental comparison of three monoclonal antibodies for the class-selective immunoextraction of triazines. Correlation with molecular modeling and principal component analysis studies. J. Chromatogr.A 999 (2003) 3-15. 

Hodgson, R. J., Brook, M. A., and Brennan, J. D., CapiUary-scale monolithic immunoaffinity columns for immunoextraction with in-line laser-induced fluorescence detection. Analytical Chemistry 77(14), 4404-4412, 2005. 

Grant, G.A., S.L. Frison, and P. Spoms. 2003. A sensitive method for detection of sulfamethazine and N4-acety lsulfamethazine residues in environmental samples using solid phase immunoextraction coupled with MALDI-TOF MS. J. Agric. Food Chem. 51 5367-5375. 

Rivasseau, C., and Hetmion M.C. 1999. Potencial of immunoextraction coupled to analytical and bioanalytical methods (liquid chromatography, ELISA kit and phosphatase inhibition test) for an improved environmental monitoring of cyanobacterial toxins. Anal ChimActa 399(13) 75-87. 

Jiang T, Mallik R, and Hage DS. Affinity monoliths for ultrafast immunoextraction. Anal. Chem. 2005 77 2362-2372. 

Highly specific antibodies have been used for a similar purpose as above in immunoextraction recycling as shown in Fig. 9.13 [66]. This technique is based on the passage of a fiuorochrome-labelled sample through a battery of small immunoaffinity columns each column extracting a single specific analyte. Detection is realized by sequential elution of bound analytes via a valve system and laser-induced fluorescence. This system was applied for selective detection of different cytokines [66]. 

The immunoextraction procedure may be off-line or on-line. In the off-line approach, the immunosorbent is packed into a disposable cartridge. A typical SPE sequence is followed. The sorbent is first conditioned, then the sample is applied, washed to eliminate interference, and analytes of interest are desorbed by the appropriate eluent system, which may be a displacer agent, a chaotropic agent, an aqueous-organic solvent mixmre, or a solution that alters pH. With the on-line approach, the immunosorbent is packed into a precolumn incorporated in a six-port switching valve, where the immunoextraction is performed at the load position, while desorption is achieved at the inject position. 

Today, the most widely used commercially available methods use acetonitrile to deproteinize the specimen and to denature DBP, thereby freeing vitamin D metabolites. A method using immunoextraction for l,25(OH)2D has also been reported. ... 

Hollis B. 1,25-Dihydroxyvitamm D3-26,23-lactone interferes in determination of 1,25-dihydroxyvitamin D by RIA after immunoextraction. CHn Chem 1995 41 1313-14. 

Direct two-step and one-step immunoassays estimate free hormone concentrations by using antibody extraction techniques. Although it is often clauned or implied that these immunoextraction assays measure FT or FT3 directly, virtually all methods do so indirectly by relating test results to extracted serum calibrators with free hormone values that have been independently measured using reference methods (e.g.,. direct equilibrium dialysis/RlA). Further, studies have shown that all of the free hormone estimate methods on current instrument platforms are binding protein dependent to some extent. ... 

Fig. 2.1. Design of solid-phase EIA. One of the immunoreactants (R or Rj, generally antibody or antigen) is immobilized on the solid phase and serves to capture the complementary reactant from the sample ( immunoextraction ). In EIA, the substance to be assayed is thus added in the second layer. Amplification of the signal of reaction between R and R is achieved with Rj which may consist of several layers.

Pichon, V., Bouzige, M., Hennion, M. C. (1998). New trends in environmental trace-analysis of organic pollutants Class-selective immunoextraction and clean-up in one step using immunosorbents. Anal. Chim. Acta, 376, 21-35. 

Bouzige, M., Legeay, P., Pichon, V., and Hennion, M. C., Selective on-line immunoextraction coupled to liquid chromatography for the trace determination of benzidine, congeners and related azo dyes in surface water and industrial effluents, J. Chromatogr., 846, 317-329, 1999. 

New methods emerge to selectively extract organophosphoms compounds from water samples without interferences. One example of this is the immunoextraction technique, at present used only for some triazines and phenylureas. " These sorbents have been obtained by covalent bonding of polyclonal antibodies to a silica matrix. The antibodies have a strong affinity for the triazines and the phenylureas. 

Bouzigue, M. and Pichon, V., Immunoextraction of pesticides at the trace level in environmental... 

Brinkman, U. A. Th., Slobodnfk, J., and Vreuls, J. J., Trace-level detection and identihcation of polar pesticides in surface water the SAMOS approach. Trends Anal. Chem., 13, 373-381, 1994. Bouzige, M. and Pichon, V., Immunoextraction of pesticides at the trace level in environmental matrices, Analusis, 26, Ml 121998. 

Figure 3 A general scheme for interfacing an immunoextraction coiumn with reversed-phase iiquid chromatography (RPLC). The two circies represent six-port switching vaives, with the soiid and dashed iines showing the fiow of sampie and soivents in each of the two positions. The operation of this system is described in the text.

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