以2-氨基-5-硝基噻唑为基质辅助激光解吸/电离飞行时间质谱的有效基质分析DNA及蛋白质样品

Analysis of Oligonucleotide and Protein via Matrix-assisted Laser Desorption/Ionization Time-of-flight Mass Spectrometry Using 2-Amino-5-nitrothiazole as an Effective Matrix

采用碱性新基质 2 -氨基 -5 -硝基噻唑对 DNA和蛋白质样品进行了基质辅助激光解吸 /电离飞行时间质谱分析 .结果表明 ,2 -氨基 -5 -硝基噻唑能有效地解吸电离 DNA和蛋白质样品 .采用正离子检测模式 ,分析分子量小于 5 0 0 0的 pd( T) 1 0 ,pd( C) 1 0 ,pd( A) 8,pd( G) 1 0 和 pd( 5′ATC GAT CGA T3′) DNA样品时 ,分辨率均可达到 1万以上 ;与分析 DNA样品的常用基质相比 ,2 -氨基 -5 -硝基噻唑解吸 /电离样品分子所需要的激光强度小 ,易于获得信噪比和分辨率高及重复性好的谱图 ;分析蛋白质胰岛素、细胞色素 C及牛血清白蛋白样品能达到与α-氰基 -4-羟基肉桂酸 ( HCCA)和 3 ,5 -二甲氧基 -4-羟基肉桂酸 ( SA)相同的效果 .采用负离子检测模式则能以较高的信噪比获得分子量达到 70 0 0的 DNA的分子离子峰信号 .此外 ,以 2 -氨基 -5 -硝基噻唑为基质的基质辅助激光解吸 /电离 ( MALDI)

Using 2-amino-5-nitrothiazole as a matrix, the matrix-assisted laser desorption/ionization time-of-flight mass spectrometric study of oligonucleotide and protein was carried out. The results show that 2-amino-5-nitrothiazole has a high efficiency in desorbing and ionizing oligonucleotide and protein molecules. In the positive-ion mode, resolution over 10 000 of pd(T) 10, pd(C) 10, pd(A) 8, pd(G) 10 and pd(5′ATC GAT CGA T 3′) can be obtained; 2-amino-5-nitrothiazole is as effective as the commonly used matrices such as α-cyano-4-hydroxycinnamic acid(HCCA) and 3, 5-dimethoxy-4-hydroxycinnamic acid(SA) for the analysis of proteins. In the negative-ion mode, the molecular ion signal of oligonucleotide with molecular mass of over 7 000 can be recorded at a high signal-to-noise ratio. Moreover, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry(MALDI-TOF-MS) analysis by utilizing 2-amino-5-nitrothiazole as a matrix shows the tolerance to alkali metal cations to a certain extent.