Methylene selectivity and eluotropic strength variations in subcritical fluid chromatography with packed columns and CO2-modifier mobile phases

摘要

This work has consisted of better understanding the chromatographic behavior in subcritical fluid chromatography with CO2-acetonitrile and CO2-methanol mobile phases. To that end, the changes of solute solubility in the mobile phase have been studied by determination of methylene selectivity of a homologous series. Moreover, eluotropic strengths have been calculated for mobile phases containing from 5 to 45% modifier. To carry out the studies in all ranges of the subcritical area, experimental designs have been used. The influences of analytical temperature (from 10 to 30 degrees C) and outlet pressure (from 10 to 20 MPa) have also been investigated both on solubility and on eluotropic strength. A more general comparison of eluotropic strengths of subFC and HPLC has been achieved. [References: 21]