香豆素类新基质在基质辅助激光解吸／电离飞行时间质谱测定多糖和糖蛋白中的应用

将几种香豆素类新基质(香豆素、3-羟基香豆素(3-HC)、3-氨基香豆素(3-AC)、3-羧基香豆素(3-CC)和4-甲基-7-羟基香豆素(4-M-7-HC))分别应用于基质辅助激光解吸/电离飞行时间质谱(MALDI TOF-MS)测定葡聚糖和3种糖蛋白的研究.香豆素和3-羟基香豆素分别与2,5-二羟基苯甲酸(DHB)混合组成2种二元基质,极大地改善了基质和葡聚糖样品的共结晶状况,样品分布更加均匀.葡聚糖样品更易解吸/电离,每个激光点照射样品均能产生较强的质谱信号,且谱图重现性更好,得到了理想的MALDI TOF-MS谱图.当香豆素类基质用于分析糖蛋白时:3-HC和4-M-7-HC是测定糖蛋白A的优异基质,能检测到m/z 为66 672 Da 的离子信号.而3-AC测定糖蛋白B的基质效果比糖类分析常用基质2,5-二羟基苯甲酸更好.因此,这些香豆素类化合物将为MALDI TOF-MS分析多糖和糖蛋白提供更多新基质选择.

Coumaric Derivatives as New Matrices for Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometric Analysis in Dextran and Glycoproteins

The coumarin and four coumaric derivatives including 3-hydroxycoumarin(3-HC),3-aminocoumarin(3-AC),3-carboxycoumarin(3-CC) and 4-methyl-7-hydroxycoumarin(4-M-7-HC) were tested as matrices for dextran and glycoproteins(glycoprotein A,glycoprotein B and glycoprotein C) by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry(MALDI-TOF MS).The results showed that the dextran molecules were desorbed and ionized more efficiently and the spot-to-spot reproducibility of spectra were enhanced when binary matrices(coumarin/dihydroxybenoic acid(DHB) and DHB/3-HC) were used respectively.It is also found that 3-HC and 4-M-7-HC have high efficiency in desorbing and ionizing glycoprotein A,and good MALDI TOF-MS spectra of glycoprotein B can be obtained when 3-AC was used as matrix.So these coumaric derivatives will be additional choices for desorbing and ionizing carbohydrates and glycoproteins more effectively.