title: Direct coupling of thin-layer chromatography-bioautography with electrostatic field induced spray ionization-mass spectrometry for separation and identification of lipase inhibitors in lotus leaves.
abstract: In situ profiling compounds in complex matrices is important technology to develop in analytic chemistry. The aim of this study is to develop a direct coupling method of thin layer chromatography (TLC) to mass spectrometry (MS) via electrostatic field induced spray ionization (EFISI). We proposed a surface treatment method of normal-phase thin layer chromatography (TLC) plates with dimethyl silicone oil coating which successfully allowed TLC to couple to MS via EFISI. Different parameters affecting the ionization efficiency were investigated and optimized, including silicone oil concentrations, air-drying times, applied voltages, and TLC plate types. This optimized TLC-EFISI-MS method was successfully applied to examine lipase inhibitory components present in lotus leaves. Six active alkaloids including three aporphines and three benzylisoquinolines were profiled with their MSn(n = 4) data, or with a comparison with reference substances. This is the first report on the coupling EFISI-MS to TLC or TLC bioautography for in situ identification of active natural products.
authors.affiliation: Key Laboratory of Standardization of Chinese Medicines of Ministry of Education, The Shanghai Key Laboratory for Compound Chinese Medicines, Institute of Chinese Materia Medica, Shanghai University of Traditional Chinese Medicine, Shanghai 201203, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Standardization of Chinese Medicines of Ministry of Education, The Shanghai Key Laboratory for Compound Chinese Medicines, Institute of Chinese Materia Medica, Shanghai University of Traditional Chinese Medicine, Shanghai 201203, China.
authors.forename: Jiyao
authors.initials: J
authors.lastname: Shi
authors.affiliation: Key Laboratory of Standardization of Chinese Medicines of Ministry of Education, The Shanghai Key Laboratory for Compound Chinese Medicines, Institute of Chinese Materia Medica, Shanghai University of Traditional Chinese Medicine, Shanghai 201203, China.
authors.forename: Jihe
authors.initials: J
authors.lastname: Tang
authors.affiliation: Department of Pharmacognosy, School of Pharmacy, Fudan University, Shanghai 201203, China. Electronic address: chengzhh@fudan.edu.cn.
authors.forename: Zhihong
authors.initials: Z
authors.lastname: Cheng
authors.affiliation: Department of Environmental Science & Engineering, Fudan University, Shanghai 200433, China.
authors.forename: Xiaohui
authors.initials: X
authors.lastname: Lu
authors.affiliation: Key Laboratory of Standardization of Chinese Medicines of Ministry of Education, The Shanghai Key Laboratory for Compound Chinese Medicines, Institute of Chinese Materia Medica, Shanghai University of Traditional Chinese Medicine, Shanghai 201203, China.
authors.forename: Yao
authors.initials: Y
authors.lastname: Kong
authors.affiliation: Key Laboratory of Standardization of Chinese Medicines of Ministry of Education, The Shanghai Key Laboratory for Compound Chinese Medicines, Institute of Chinese Materia Medica, Shanghai University of Traditional Chinese Medicine, Shanghai 201203, China. Electronic address: laurawu2000@163.com.
authors.forename: Tao
authors.initials: T
authors.lastname: Wu
mesh_terms: D000470:Alkaloids / Q000032:analysis*; D002855:Chromatography, Thin Layer; D008049:Lipase / Q000037:antagonists & inhibitors*; D031653:Nelumbo / Q000737:chemistry*; D018515:Plant Leaves / Q000737:chemistry*; D021241:Spectrometry, Mass, Electrospray Ionization
chemical_list: D000470:Alkaloids; D008049:Lipase
keywords: Ambient ionization; Bioautography; Electrostatic field induced spray ionization; Lipase inhibitor; Nelumbo nucifera; Thin-layer chromatography-mass spectrometry