title: Application of fractionized sampling and stacking for construction of an interface for online heart-cutting two-dimensional liquid chromatography.
abstract: In this study, an efficient interface, based on a fractionized sampling and stacking (FSS) strategy, was developed for online heart-cutting two-dimensional liquid chromatography (2D LC). This interface consisted of a two-position 4-port valve, a two-position 6-port valve and a two-position 10-port valve equipped with two 450-μL stainless steel loops. Hydrophilic interaction chromatography (HILIC) and reversed phase liquid chromatography (RP LC) were used in the first and second dimensions, respectively. The peak compression efficiency of this interface was investigated by analysis of ten standards. Good peak shapes of the ten standards were observed when the dilution ratio was over five and the co-eluate plug volume was less than 10μL. The 2D LC system was further applied to analysis of a crude extract of Panax ginseng leaves. Seventeen major constituents in the extract were monitored, which could not be well separated by one-dimensional (1D) HILIC or RP LC method in a long separation gradient. The FSS interface successfully achieved the efficient combination of HILIC and RP LC, and the 17 constituents in ginseng extract got well separated under the optimized conditions. The FSS interface has shown great potential for 2D LC analysis of complex natural product samples.
authors.affiliation: Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, PR China.
authors.forename: Baocheng
authors.initials: B
authors.lastname: Ji
authors.affiliation: Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, PR China. Electronic address: xiabing@cib.ac.cn.
authors.forename: Bing
authors.initials: B
authors.lastname: Xia
authors.affiliation: Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, PR China.
authors.forename: Jie
authors.initials: J
authors.lastname: Liu
authors.affiliation: Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, PR China.
authors.forename: Yuanji
authors.initials: Y
authors.lastname: Gao
authors.affiliation: Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, PR China.
authors.forename: Lisheng
authors.initials: L
authors.lastname: Ding
authors.affiliation: Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, PR China. Electronic address: zhouyan@cib.ac.cn.
authors.forename: Yan
authors.initials: Y
authors.lastname: Zhou
mesh_terms: D002623:Chemistry Techniques, Analytical / Q000295:instrumentation* / Q000379:methods*; D056148:Chromatography, Reverse-Phase; D057927:Hydrophobic and Hydrophilic Interactions; D005894:Panax / Q000737:chemistry; D010936:Plant Extracts / Q000302:isolation & purification*; D018515:Plant Leaves / Q000737:chemistry
chemical_list: D010936:Plant Extracts
keywords: 2D LC; Fractionized sampling and stacking strategy; Heart-cutting; Interface