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Biomedical subjects

Valérie Pichon

Publications and source records attributed to Valérie Pichon.

2 recordsLinked to original sources

Immuno-based sample preparation for trace analysis.

Immuno-based sample preparation techniques are based upon molecular recognition. Thanks to the high affinity and high selectivity of the antigen-antibody interaction, they have been shown to be a unique tool in the sampling area. Immuno-based sample preparation methods include the widely encountered immunoaffinity extraction sorbents, so-called immunosorbents, as well as membrane-baed or ultrafiltration techniques. This review describes the new developments and applications that have occurred in recent years with emphasis on (i) the antigen-antibody interactions, (ii) and their importance for the properties and use of immunosorbents, (iii) multiresidue extractions, (iv) the on-line coupling to chromatographic or electrophoretic separations, and (v) the high potential for improving MS detection. The recent use of artificial antibodies for sample pretreatment, so-called molecularly imprinted polymers, is also described.

Antigen-Antibody Reactions↗

Experimental comparison of three monoclonal antibodies for the class-selective immunoextraction of triazines. Correlation with molecular modeling and principal component analysis studies.

The specificity of three immunosorbents (ISs) based on different monoclonal anti-triazine antibodies has been characterized by extraction recoveries studies and with step elution experiments. Both indicated that the anti-dichloroatrazine IS is specific of terbutylazine and cyanazine. The anti-atrazine IS is specific of the chlorotriazines, whereas the anti-ametryn IS can trap all the triazines. This confirms the great influence of the hapten design on the specificity of the resulting antibodies, even if the target molecules are small. Moreover, the anti-ametryn IS is suitable for class-selective extraction of triazines contained in complex matrices. An approach designed to learn more about the specificity for a group of structurally related compounds of antibodies produced with a given compound is proposed and evaluated. Molecular modeling followed by principal component analysis has been used to obtain distribution maps with the relative position of each immunoconjugate and all the triazines. In all three cases, conclusions on specificity made with the analysis of the maps fit well with the experimental results. Consequently, molecular modeling coupled with principal component analysis seems to be a unique, inexpensive, and rapid tool to select the appropriate hapten providing highly specific or class-specific antibodies according to the given problem.

Antibodies, Monoclonal↗