NORMAL-PHASE HIGH-PERFORMANCE LIQUID CHROMATOGRAPHY USING ENHANCED-FLUIDITY LIQUID MOBILE PHASES

摘要

The application of an enhanced-fluidity liquid mixture (n-hexane-CO,) as a mobile phase in normal-phase HPLC using a 3-cyanopropyl polysiloxane stationary phase was evaluated. Decreased pressure drop across the chromatographic column was observed with increasing proportions of added CO2 to the mixtures. For selected mixture conditions, increased efficiency and decreased peak asymmetry were obtained in comparison to that for separations with 100% n-hexane. A limiting amount of CO2 that could be added to hexane was found. If more CO2 was added past that limit, serious peak asymmetry lowered the measured column efficiency. [References: 24]