Chapter 1 General Detection Problems in SFC

Abstract

Publisher Summary This chapter presents the general detection problems faced in supercritical fluid chromatography (SFC). When the separation stage of a hyphenated system is SFC, special interfacing problems exist between the SFC and the spectrometer due to the unique properties of super critical fluids. Phase changes, varying sample introduction rates, mobile phase compatibility, mobile phase elimination, integrity of the SFC separation, and ambiguous detector terminology are all problems with SFC hyphenated analytical methods. Perhaps the most difficult problem associated with SFC detection is compatibility with the mobile phase. Carbon dioxide has emerged as one of the principal mobile phases used in SFC not only because of its convenient critical parameters and non-toxicity but also because of its compatibility with both flame ionization and UV absorption detection. Nevertheless, the use of modifiers with CO 2 to increase polarity is severely limited by the detection method employed. Comparative evaluation of hyphenated detection methods for SFC can also present a problem since such a wide variety of analytical methods can be interfaced with SFC.