Investigation of anion-exchange and immunoaffinity particle-loaded membranes for the isolation of charged organic analytes from water

T. R. Dombrowski; G.S. Wilson; E.M. Thurman

doi:10.1021/ac971081t

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Investigation of anion-exchange and immunoaffinity particle-loaded membranes for the isolation of charged organic analytes from water

T. R. Dombrowski·G.S. Wilson·E.M. Thurman

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Abstract

Anion-exchange and immunoaffinity particle loaded membranes (PLMs) were investigated as a mechanism for the isolation of charged organic analytes from water. Kinetic properties determined theoretically included dynamic capacity, pressure drop (Δ P ), residence and diffusion times ( T r , T d ), and total membrane porosity (ε T ). These properties were confirmed through experimental evaluation, and the PLM method showed significant improvement over conventional solid-phase extraction (SPE) and ion-exchange formats. Recoveries of more than 90% were observed for a variety of test compounds at flow rates up to 70 mL/min (equipment-limited maximum flow rate). A fast-flow immunoaffinity column was developed using antibodies (Abs) attached to the PLMs. Reproducible recoveries (88% ± 4%) were observed at flow rates up to 70 mL/min for the antibody (Ab)-loaded PLMs. Findings indicate increased selectivity over anion-exchange PLMs and conventional SPE or ion-exchange methods and rapid Ab−antigen binding rates given the excellent mass-transfer characteristics of the PLMs.

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T. R. Dombrowski, G.S. Wilson, E.M. Thurman. 1998-04-01. Investigation of anion-exchange and immunoaffinity particle-loaded membranes for the isolation of charged organic analytes from water. https://doi.org/10.1021/ac971081t

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