The application of on-line two-dimensional liquid chromatography (2DLC) in the chemical analysis of herbal medicines

Herbal medicines are complicated chemical systems containing hundreds of small molecules of various polarities, structural types, and contents. Thus far, the chromatographic separation of herbal extracts is still a big challenge. Two-dimensional liquid chromatography (2DLC) has become an attractive separation tool in the past few years. Particularly, a lot of attention has been paid to on-line 2DLC. In this review, we aim to give an overview on...