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Updated: May 10, 2026

2D-HPLC-MS Technology Combined with Molecular Network for the Identification of Components in Tibetan Medicine Aconitum pendulum
Published on: December 8, 2023
Use of shift gradient in the second dimension to improve the separation space in comprehensive two-dimensional liquid
1Applied Analytical Chemistry, Faculty of Chemistry, University of Duisburg-Essen, Essen, Germany.
Abstract:
Comprehensive two-dimensional liquid chromatography (LC × LC) has received much attention because it offers much higher peak capacities than separation in a single dimension. The advantageous peak capacity makes it attractive for the separation of complex samples. Various gradient methods have been used in LC × LC systems. The use of continuous shift gradient is advantageous because it combines the peak compression effect of full gradient mode and the tailed gradient program in parallel gradient mode. Here, a comparison of LC × LC analysis of Chinese herbal medicine with full gradient mode and shift gradient mode in the second dimension was performed. A correlation between the first and second dimensions was found in full gradient mode, and this was significantly reduced with shift gradient mode. The orthogonality increased by 43.7%. The effective peak distribution area increased significantly, which produced better separation.
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