Chemometric approach for development, optimization and validation of HILIC methods used for the determination of alkaloids from poppy straw

Abstract

Two hydrophilic interaction liquid chromatography (HILIC) methods for simultaneous determination of the major alkaloids (morphine, codeine, thebaine, oripavine, papaverine and noscapine) in opium poppy straw (Papaver somniferum L., Papaveraceae) were developed. The chromatographic behavior of target alkaloids was investigated on two different HILIC stationary phases: bare silica (Si-HILIC) and zwitterionic (ZIC-HILIC). Systematic optimization of the methods was carried out by use of chemometrics. A full factorial design of the experiments was utilized for assessment of the influence of acetonitrile share, ionic strength and the pH value of the mobile phase buffer on several chromatographic responses. The central composite circumscribed design of experiments was used for the robustness testing during the method validation. The separation of the alkaloids was obtained within close retention window on both columns with optimized gradient elution. The ZIC-HILIC method had advantage over Si-HILIC method in terms of sensitivity, robustness and cost. This method was found suitable for determination of the morphinane alkaloids from poppy straw.

Keywords

• chemometry, design of experiments, hilic/dad, opium poppy alkaloids