Solid-phase extraction in clinical biochemistry

• Published in: Annals of Clinical Biochemistry 2002-09, Vol.39 (5), p.464-477
• Main Authors: WALKER, Valerie, MILLS, Graham A
• Format: Article
• Language: English
• Subjects: Adsorption; Animals; Automation; Biochemistry; Biological and medical sciences; Chemistry Techniques, Analytical - methods; Chemistry Techniques, Analytical - trends; Chemistry, Clinical - instrumentation; Chemistry, Clinical - methods; Humans; Investigative techniques, diagnostic techniques (general aspects); Medical sciences; Miscellaneous. Technology; Pathology. Cytology. Biochemistry. Spectrometry. Miscellaneous investigative techniques
• ISSN: 0004-5632; 1758-1001
• DOI: 10.1258/000456302320314476

In order to measure low concentrations of analytes in plasma and urine, it is often necessary to extract and concentrate them. With solid-phase extraction (SPE), this is achieved by partitioning the analytes between a solid and a liquid or headspace vapour. A wide range of high-quality materials is now available to do this, offering a variety of separation modes for different applications. These include partitioning using reversed-phase, normal-phase, ion-exchange, restricted-access and immunoaffinity sorbents or molecularly imprinted polymers and, increasingly, combinations of these processes. Solid-phase microextraction was introduced to analyse volatile and semi-volatile compounds. The range of sampling formats has expanded from simple packed syringes to cartridges, disks, SPE pipette tips and 96-well plates. These developments have facilitated automated off- and on-line sample processing. The basic principles of SPE and the recent innovations are reviewed here. This is a technological growth area. Some of the developments are finding application in clinical toxicology. However, they could also be of wider value in clinical chemistry - for example, for analyses of volatile and non-volatile metabolites, peptides, radioactive elements and trace metal speciation.