Tuning of mobile and stationary phase polarity for the separation of polarcompounds by SFC

The separation of polar compounds by supercritical-fluid chromatography (SF C) is reviewed. New developments in mobile and stationary phase tuning are reviewed for packed and packed capillary SFC. In terms of mobile phase pola rity adjustment, new pure and multiple component fluids are presented. The approach of tuning the polarity of the stationary phase as a way of increas ing the range of polar compounds analyzed by SFC using pure CO, is discusse d using either silica-based or new materials as stationary phase. Chiral, l iquid crystal and polymer-based stationary phases coated on particles are w idely covered in this review as an interesting approach to separate polar c ompounds avoiding the major drawbacks associated to the use of modifiers in SFC. (C) 2000 Elsevier Science B.V. All rights reserved.