TEMPERATURE EFFECTS FOR CHIRAL SEPARATIONS USING VARIOUS BULK FLUIDS IN NEAR-CRITICAL MOBILE PHASES

As supercritical fluid chromatography becomes more accepted as a facil e means for the separation of chiral compounds, the need for mobile ph ases that can readily solubilize these polar compounds grows. Prior st udies suggest that HFC-134a may prove suitable due to its very high el uotropic strength compared to carbon dioxide-based mobile phases. A co mparison is made between ethanol-modified carbon dioxide, HFC-134a, an d decafluoropentane as to their relative eluotropic strength, selectiv ity, and efficiency for three chiral compounds using a Whelk O-1 chira l bonded phase. The bulk component of the mobile phase was found to ha ve relatively little effect on chiral selectivity over the range of 5 degrees to 95 degrees C. (C) 1997 Wiley-Liss, Inc.