Fast Atom Bombardment Mass Spectrometry: Matrix Effects on Ion Formation and Fragmentation
Fast Atom Bombardment Mass Spectrometry: Matrix Effects on Ion Formation and Fragmentation
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快原子轰击质谱：基质对离子形成和碎裂的影响
DOI：
10.5702/massspec.42.249
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发表时间：
1994
期刊：
影响因子：
--
通讯作者：
M. Takayama
中科院分区：
文献类型：
--
作者：
M. Takayama
利用各种有机化合物描述了基质对快原子轰击（FAB）条件下产生的M+·和[M+H]+离子的竞争形成和碎裂程度的影响，以及对FAB条件下形成的复合物[M+基质+H]+和[M+基质-H]-离子的影响。与使用疏水性基质如间硝基苯甲醇和邻硝基苯基辛基醚相比，使用亲水性基质如甘油和硫代甘油导致[M+H]+至M+·离子的优先形成。与使用含巯基的亲水性基质如硫代甘油和二硫苏糖醇相比，使用醇-亲水性基质如甘油和五亚甲基二醇导致[M+H]+至M+·离子的优先形成。根据羟基-OH和巯基-SH之间氢键作用能力的差异解释了后者的基质效应，提出基质溶液中基质羟基与分析物分子碱性位点之间的氢键作用（称为“准预成态”）有利于[M+H]+到M+·离子的形成。证实了在FAB条件下产生的[M+H]+和M+·离子的碎裂彼此独立地发生，并且M+·离子的碎裂程度通常与在电子碰撞电离方法中在70 eV或更高处形成的M+·离子的碎裂程度相当。在FAB条件下，M+·离子的碎裂程度取决于所使用的基质材料。此外，在FAB条件下的[M+H]+离子的碎裂程度大于由异丁烷化学电离方法形成的[M+H]+离子的碎裂程度。络合离子[M+matrix+H]+和[M+ matrix-H]-是通过使用某种异戊烯化的黄酮和含巯基的基质形成的，而络合离子不是通过使用缺少异戊烯基的黄酮或甘油基质形成的。讨论了基质材料对正离子和负离子FAB质谱的适用性.
Matrix effects on the competitive formation and extents of fragmentation of M+· and [M+H]+ ions produced under fast atom bombardment (FAB) conditions, and on the formation of complex [M+matrix+H]+ and [M+matrix-H]- ions under FAB conditions have been described using various organic compounds. The use of hydrophilic matrices such as glycerol and thioglycerol resulted in the preferential formation of [M+H]+ to M+· ions compared to the use of hydrophobic matrices such as m-nitrobenzyl alcohol and o-nitrophenyloctyl ether. The use of alcoholic-hydrophilic matrices such as glycerol and pentamethylene glycol resulted in the preferential formation of [M+H]+ to M+· ions compared to the use of thiol-containing hydrophilic matrices such as thioglycerol and dithiothreitol. The latter matrix effect was explained on the basis of the distinction of hydrogenbonding ability between hydroxyl -OH and thiol -SH groups, and it was proposed that the hydrogen-bonding interaction between the hydroxyl group(s) of matrix and the basic site(s) of analyte molecules in matrix solution, which was named as a ‘quasi-preformed state’, is advantageous for the formation of [M+H]+ to M+· ions. It was confirmed that the fragmentation of [M+H]+ and M+· ions produced under FAB conditions occurs independently to each other and that the extent of fragmentation of M+· ions is often comparable to that of fragmentation of M+· ions formed at 70 eV or above in the electron impact ionization method. The extent of fragmentation of M+· ions under FAB conditions depended upon the matrix materials used. Further, the extent of fragmentation of [M+H]+ ions under FAB conditions was larger than that of fragmentation of [M+H]+ ions formed by the isobutane chemical ionization method. The complex ions, [M+matrix+H]+ and [M+matrix-H]-, were formed by the use of a certain prenylated flavone and thiol-containing matrices, while the complex ions were not formed by the use of the flavone lacking a prenyl group or glycerol matrix. The suitability of matrix materials for positive- and negative- ion FAB mass spectrometry has been discussed.