Commercial instruments have been available since 1988, and systems are currently available from over 20 suppliers. Recent survey papers have considered the relative performance and features of these commercial systems (1,2). Systems are available in both single bench-top units or in modular form. Figure 1 shows a photograph of a commercial unit. Currently the CE equipment market is dominated by the major HPLC instrument supply companies, such as Beckman (Fullerton, CA), Hewlett Packard (Waldbronn, Germany), Perkin Elmer (Foster City, CA), and Waters (Milford, MA).