On-line coupling of automatic solid-phase extraction and HPLC for determination of carotenoids in serum

Abstract

The automated method developed for the determination of carotenoids uses 200μL of serum, which was mixed with 400μL of tetrahydrofuran, vortexed for 1min, settled for 10min, centrifuged for 6min and the supernatant injected into an automatic solid-phase extraction (SPE) system for cleanup–preconcentration. A 10% water–acetonitrile mobile phase at 1.5mLmin−1 eluted the retained compounds and transferred them on-line to a reversed-phase analytical column for individual separation of the target analytes. Visible detection was performed at 450 and 460nm. The detection limits for the target analytes were between 3 and 30ngmL−1; the precision (expressed as relative standard deviation) ranged between 2.83 and 5.06% for repeatability and between 3.80 and 7.40% for within laboratory reproducibility. The total analysis time was 18min. The proposed method is reliable, robust, and has an excellent potential for high-throughput use in both clinical and research laboratories.