Determination of carotenoids in microalgae using supercritical fluid extraction and chromatography.

A method was developed based on supercritical fluid chromatography for quantitative determination of carotenoids in extracts of Scenedesmus sp. By utilizing the low backpressure in supercritical fluid chromatography, a C18 column and a 2-ethyl pyridine column were coupled in series. It was concluded that even minor changes in temperature had a substantial effect on selectivity. A standard mixture of 8 carotenoids and microalgae extracts obtained through supercritical fluid extraction with and without 10% ethanol as a co-solvent were successfully separated. All of the carotenoids were separated within 10 min, while the total analysis time was 20 min. The method was validated and the carotenoids of microalgae extracts were quantified. Furthermore, the method should be seen as a more rapid and environmentally sustainable alternative to traditional high-performance liquid chromatography methods utilizing organic solvents.