León-González M E, Pérez-Arribas L V
Departamento de Química Analítica, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, Spain.
J Chromatogr A. 2000 Dec 1;902(1):3-16. doi: 10.1016/s0021-9673(00)00942-0.
Solid-phase extraction is an attractive alternative in sample preparation because it overcomes many drawbacks of liquid-liquid extraction and makes on-line determination possible by hyphenation with chromatographic techniques. Driven by the need for more effective and more selective sorbents, advances in solid-phase extraction include the development of new materials. This paper describes different types of chemically modified sorbents for the solid-phase extraction of compounds from aqueous samples. Chemical introduction of different functional groups into a polymeric resin improves the efficiency of solid-phase extraction by providing better surface contact with the aqueous samples; also, these sorbents have a greater capacity than the typical solid-phase materials for polar compounds have. The most important new sorbents are the chemically modified resins based on styrene-divinylbenzene copolymers. Preparation of these new sorbents is described, and advantages and drawbacks of off-line procedures and on-line procedures are also discussed. Applications for off-line and on-line chromatographic determinations of polar compounds are presented.
