SPECIFIC EFFECTS OF MODIFIERS IN SUBCRITICAL FLUID CHROMATOGRAPHY OF CAROTENOID-PIGMENTS

The use of subcritical fluid chromatography with filled columns for th e analysis of carotenoid pigments affords a threefold reduction in ana lysis times with respect to HPLC. The addition of modifiers to CO2 inc reases the solubility of pigments in the mobile phase. This paper repo rts the influence of modifiers on the separation of carotenoids in ter ms of specific interactions, such as hydrogen bonding and pi-pi intera ctions between the solvent and the solute. The understanding of these interactions allowed the optimization of the separation of seven carot enoids and some of their cis isomers; this separation required less th an 20 min.