Advances in online two-dimensional liquid chromatography for natural product screening

As a treasure resource of novel drug lead compounds, how to rapidly and high-efficiently screen and isolate active components from natural products is critical. Thanks to its high resolution, high automation and flexible integration, online two-dimensional liquid chromatography has great potential for screening active ingredients from complex matrices by integrating a highly specific bio-recognition process into a two-dimensional liquid chromatography system before, on or after the column separation. This review comprehensively summarized recent developments, applications and shortcomings of online two-dimensional liquid chromatography for natural product screening from different integration modes, including pre-column, on-column and post-column screening methods.