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

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

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(MALDITOF-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MALDITOF-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66672Da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MALDITOF-MS分析多糖和糖蛋白提供更多新基质选择。

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 glyeoproteins （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.