基于离子液体的基质辅助激光解吸电离质谱成像分析桑叶表面和叶脉切片中的小分子成分  

Matrix-assisted Laser Desorption Ionization-Mass Spectrometry Imaging of Small Molecules in Mulberry Leaf Using Ionic Liquid as Matrix

作　　者：刘晓宁 裴兴丽 龚灿 许旭 LIU Xiao-Ning;PEI Xing-Li;GONG Can;XU Xu(School of Chemical and Environmental Engineering,Shanghai Institute of Technology,Shanghai 201418,China)

机构地区：[1]上海应用技术大学化学与环境工程学院,上海201418

出　　处：《分析化学》2018年第12期1923-1930,共8页Chinese Journal of Analytical Chemistry

基　　金：国家自然科学基金项目(No.31671928);上海市自然科学基金项目(No.15ZR1440800)资助~~

摘　　要：结合离子液体基质2,5-二羟基苯甲酸/N,N-二甲基苯胺(DHB/DMA)与超声喷雾基质覆盖方法,用基质辅助激光解吸电离质谱(MALDI-MS)分析桑叶表面和叶脉中的原儿茶酸、绿原酸、单糖和二糖、黄芪苷、芦丁、异槲皮素、矢车菊素-3-O-葡糖苷、槲皮素-3-O-6"-O-乙酰基-β-D-吡喃葡萄糖苷和山奈酚-3-O-芦丁糖苷等小分子成分,并进一步通过质谱成像显示这些成分在桑叶样品中的空间分布。3种基质覆盖方法(干滴法、喷枪法、超声喷雾法)比较结果表明,超声喷雾覆盖法具有较好的重现性和灵敏度,而且不易引起待测成分的扩散。在考察实验条件对信噪比影响的基础上,选择激光能量为70%、超声喷雾重复喷涂12次、添加剂KBr浓度为7.5 mmol/L的实验条件,用MALDI-MS成像分析了桑叶表面和叶脉切片中不同小分子成分的分布。结果表明,基于离子液体基质和超声喷雾基质覆盖的方法可用于中药和植物中小分子成分的MALDI-MS成像分析,效果良好。Ionic liquid matrix 2,5-dihydroxybenzoic acid/N,N-dimethylaniline(DHB/DMA)and ultrasonic spray deposition method were selected for matrix-assisted laser desorption ionization-mass spectrometry(MALDI-MS)analysis and MALDI-MS imaging of small molecule components on the surface of mulberry leaf and in leaf vein,including protocatechuic acid,chlorogenic acid,monosaccharide and disaccharide,astragalin,rutin,isoquercetin,cyanidin-3-O-glucoside,quercetin-3-O-6”-O-acetyl-β-D-glucopyranoside and kaempferol-3-O-rutinoside.The ultrasonic spray method was performed to deposit the ionic liquid matrix on sample slice with less diffusion of the analytes and improved reproducibility and sensitivity compared with spotting method and airbrush deposition method.The experimental conditions were optimized according to their effects on signal-to-noise ratio,and as a result,laser energy of 70%,ultrasonic spray 12 times,and 7.5 mmol/L additive KBr were selected.The distributions of different components on the surface of mulberry leaf or in leaf vein slice were analyzed by MALDI-MS imaging.The result suggested that the ionic liquid matrix and ultrasonic spray deposition matrix method could be well applied in MALDI-MS imaging of small molecular components in traditional Chinese medicine or plant.

关 键 词：质谱成像 离子液体基质 桑叶 植物代谢物 超声喷雾 

分 类 号：O657.63[理学—分析化学]