Optimization of Micellar Electrokinetic Chromatographic Separation of Aporphine Alkaloids By Overlapping Resolution Mapping

Abstract

Based on previous work using the uni-variate approach to optimize the separation of nine Lauraceous aporphine alkaloids, lindcarpine, laurolitsine, N-methyllindcarpine, boldine, norpredicentrine, isocorydine, laurotetanine, N-methyl-laurotetanine, and isoboldine, by micellar electrokinetic chromatography, a three-parameter overlapping resolution mapping (ORM) scheme was employed to optimize the separation of these compounds. With the other conditions preoptimized, three buffer parameters, i.e., the concentrations of sodium borate, sodium dodecylsulfate, and sodium heptanesulfonate were chosen to carry out the optimization process. Conditions were identified that allowed base-line separation of the nine aporphines and the internal standard within eight minutes. These results show that ORM is an efficient optimization procedure, although some primary separation data is first required.