Carotenoid reversed-phase high-performance liquid chromatography methods : reference compendium

Publisher Summary This chapter discusses high-performance liquid chromatographic (HPLC) methods for separation of carotenoids. No single HPLC separation is capable of separating all natural carotenoids. Therefore, more than one technique may be necessary to accomplish the degree of separation required. Carotenoid separations are performed by both normalphase HPLC (NPLC) and reversed-phase HPLC (RPLC). NPLC encompasses adsorptive phases (such as silica and alumina) and polar bonded phases (such as, alkylamine, alkylnitrile, and alkyl glycol) in conjunction with nonpolar mobile phases. Polar sites on the carotenoid molecules compete with solvent modifiers for adsorptive sites on the stationary phase. In addition, both NPLC and RPLC can be run with the same solvent throughout (isocratic elution), or with solvent composition changing during the run (gradient elution). These distinctions are noted because the subsequent methods of analysis are limited to isocratic and gradient elution RPLC.