On‐line HPLC‐HRGC coupling and simultaneous transfer of two different LC fractions: Determination of aliphatic alcohols and sterols in olive oil

Abstract

Abstract A modified loop‐type interface is decribed which uses two 6‐way valves and concurrent eluent evaporation to perform an on‐line transfer and simultaneous gas chromatographic analysis of two different fractions pre‐separated by liquid chromatography. The interface is used to simultaneously analyze aliphatic alcohols and sterols present in olive oil. LC pre‐separation is carried out using a normal phase column (20 cm × 0.21 cm i.d.) and hexane‐isopropanol (99:1) as a mobile phase at a flow of 0.2 ml/min; for the GC analysis a 5 % phenyl, 95 % dimethyl siloxane (25 m × 0.32 mm i.d., 0.4 μm film thickness) column is used.