RECENT ADVANCES IN DISK-FORMAT SOLID-PHASE EXTRACTION

Disk formats for solid-phase extraction (SPE) provide a unique class o f sample preparation products. Extraction devices in a disk format are nonchanneling, high-capacity and efficient extraction media with a la rge cross-sectional area-to-volume ratio. Disk characteristics include low bed masses (for retention selectivity) and low void volumes. Redu ced-bed-mass disks retain analytes efficiently and minimize the nonspe cific adsorption associated with conventional packed-bed SPE columns. The low void volumes of SPE disks reduce the reagent volume requiremen ts for sample processing. The availability of different chemically mod ified surfaces ensures maximum extraction selectivity. By choosing the proper surface chemistry, users can optimize their extraction procedu res.