Related Experiment Video
Updated: Jan 22, 2026

Post Column Derivatization Using Reaction Flow High Performance Liquid Chromatography Columns
Published on: April 26, 2016
Development of an At-Column Dilution Modulator for Flexible and Precise Control of Dilution Factors to Overcome
Yingzhuang Chen1, Junjie Li, Oliver J Schmitz
1Key Laboratory of Phytochemical R&D of Hunan Province, Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research, Ministry of Education , Hunan Normal University , Changsha 410081 , China.
Abstract:
With the combination of different mechanisms, two-dimensional liquid chromatography has brought revolutionary changes compared to the traditional one-dimensional separation, which dramatically improve the peak capacity in separation and meet the ever-increasing demand for the analysis of complex samples in different research fields, such as chemistry, medicine, etc. However, the incompatibilities between two columns due to the transport of the large sample volume and the solvent effect always limit the wide use of two-dimensional liquid chromatography. In order to resolve this problem an at-column dilution (ACD) modulator was established to overcome the solvent incompatibility in the orthogonal combination within the comprehensive two-dimensional liquid chromatography. This interface is modified from normal two-dimensional interfaces by an additional transfer pump, which realize the at-column dilution without a flow split during the transportation. Moreover, with the control of the transfer flow and the second-dimensional gradient flow, it is able to precisely regulate the at-column dilution factor and conveniently optimize the separation conditions in both dimensions. In this work, a systematic research has been done between the setups with/without the at-column interface in the combination of reversed-phase liquid chromatography and hydrophilic interaction chromatography (RPLC × HILIC) and HILIC × RPLC, which proved that the at-column interface is able to resolve the solvent conflict problem very well. Furthermore, red ginseng was chosen as a real sample to investigate the applicability of the at-column dilution modulator for comprehensive two-dimensional chromatography with high orthogonality.
More Related Videos
10:14Chromatographic Fingerprinting by Template Matching for Data Collected by Comprehensive Two-Dimensional Gas Chromatography
Published on: September 2, 2020
11:17Multiplex Therapeutic Drug Monitoring by Isotope-dilution HPLC-MS/MS of Antibiotics in Critical Illnesses
Published on: August 30, 2018
Related Concept Videos
Solution Concentration and Dilution
Formation of Dilute Urine
Filtrate Osmolarity in the PCT
Initially, as the filtrate passes through the proximal convoluted tubule (PCT), its...
Gas Chromatography: Types of Columns and Stationary Phases
For an analyte to remain on the column for a sufficient amount of time, it must exhibit some level of compatibility (or...
Physiology of the Genitourinary System III: Urine Concentration and Dilution
Types Of Column Chromatography
Gel Filtration Chromatography
When the...
Diffusion on Chromatography Columns
Longitudinal diffusion occurs when the solute molecules in the mobile phase diffuse from the more concentrated center of the chromatographic band to the more dilute regions on either side, both towards and against the flow direction. This...