Analysis of flavonoids in leaves of Adinandra nitida by capillary electrochromatography on monolithic columns with stepwise gradient elution

Abstract

Extracts of Adinandra nitida leaves, known as Shiyacha in China, were analyzed by monolithic columns of capillary electrochromatography (CEC). To obtain good resolution within a short time, stepwise gradient elution of CEC was employed, and the effects of experimental parameters, such as the buffer, the gradient conditions, and the mode of injection were studied systematically. Under optimized conditions, analysis could be accomplished in 25 min on a monolithic rod of macroporous poly(butyl methacrylate-co-ethylene dimethacrylate). With two identified flavonoids, epicatechin and apigenin, as markers, a quality control method for Shiyacha and its relevant products was established. The calibration curves exhibited good linear behavior over the concentration range of two orders of magnitude. On combination with an on-line concentration technique, the detection limit of flavonoids could be decreased to 25 ng for apigenin.

Extraction, separation, and detection methods for phenolic acids and flavonoids

“…By this means, good resolution was obtained within a short time [195]. Huang et al compared microemulsion electrokinetic chromatography with MEKC methods for the analysis of phenolic compounds [196].…”

Application of MEKC and monolithic CEC for the analysis of bioactive naphthoquinones in Eleutherine americana

“…A hydrophilic monolith according to Lin et al [3] consisting of glycidyl methacrylate, ethylene dimethacrylate and 3-sulfopropyl methacrylate potassium salt as monomers and DMF and 1,4-butanediol as porogen; a hydrophobic monolith with ethylene dimethacrylate, butyl methacrylate and 2-acrylamido-2-methylpropanesulfonic acid as functional monomer with a porogenic system consisting of water, 1-propanol, and 1,4-butanediol [4], and finally a monolith in analogy to that described by Augustin et al [19]. This material bears strong cationic quaternary ammonium functionalities, providing an anodic flow in the entire pH range.…”

“…For recently developed techniques, such as CEC using monolithic separation materials, mostly systematic studies have been performed. In this respect only a limited number of practical applications is available in the literature [3][4][5][6][7].…”

Recent Applications of Capillary Electrophoresis in the Analysis of Traditional Chinese Medicines

“…In this case, porogens act as an emulsifier and create the porous structure. Zhang et al [120] prepared a poly(butyl methacrylate-co-ethylene dimethacrylate (BMA-EDMA) monolithic column for the analysis of flavonoids in leaves of Adinandra nitida by CEC with stepwise gradient elution. Guo et al [121] prepared BMA-EDMA monolithic column for the determination of cytidine and adenosine in cordyceps.…”