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Application of mixed-mode, solid-phase extraction in environmental and clinical chemistry. Combining hydrogen-bonding, cation-exchange and Van der Waals interactions

M. S. Mills·E.M. Thurman·M.J. Pedersen
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Abstract

Silica- and styrene-divinylbenzene-based mixed-mode resins that contain C8, C18 and sulphonated cation-exchange groups were compared for their efficiency in isolation of neutral triazine compounds from water and of the basic drug, benzoylecgonine, from urine. The triazine compounds were isolated by a combination of Van der Waals and hydrogen-bonding interactions, and benzoylecgonine was isolated by Van der Waals interactions and cation exchange. All analytes were eluted with a polar organic solvent contaning 2% ammonium hydroxide. Larger recoveries (95%) were achieved on copolymerized mixed-mode resins where C18 and sulfonic acid are in closer proximity than on 'blended' mixed-mode resins (60-70% recovery).

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M. S. Mills, E.M. Thurman, M.J. Pedersen. 1993. Application of mixed-mode, solid-phase extraction in environmental and clinical chemistry. Combining hydrogen-bonding, cation-exchange and Van der Waals interactions. https://doi.org/10.1016/0021-9673(93)80349-d

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