Matrix-enhanced secondary ion mass spectrometry: Effects of aliphatic carboxylic acid matrices on the sensitivity enhancement of biological phospholipids
Matrix-enhanced secondary ion mass spectrometry: Effects of aliphatic carboxylic acid matrices on the sensitivity enhancement of biological phospholipids
复制标题
基质增强二次离子质谱：脂肪族羧酸基质对生物磷脂灵敏度增强的影响
DOI：
10.1002/sia.7212
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发表时间：
2023
影响因子：
1.7
通讯作者：
Rie Shishido
中科院分区：
文献类型：
--
作者：
渡邊 拓実;佐々木悠人;Smita Takawane;姜偉華;大場友則;Rie Shishido
基质增强二次离子质谱法（ME - SIMS）是一种有效的预处理方法，用于提高大分子的灵敏度。近年来，利用这一技术开发了由芳香酸和苯环组成的基质辅助激光解吸/电离（MALDI）基质。然而，SIMS和MALDI在解吸和电离过程中存在一些差异。在这项研究中，使用双簇飞行时间模拟模拟（TOF - SIMS）研究了与脂肪族羧酸混合的磷脂的敏感性。反乌头酸（三羧酸）和柠檬酸（羟基羧酸）作为基质。选取典型芳香型MALDI基质2,5‐二羟基苯甲酸（DHB）作为参比基质。当以乌头酸和DHB为基质时，[M + H]+和[2 M + H]+对磷脂的二次离子产率比原始脂质高约10-150倍。对于添加柠檬酸的样品，[M + H]+和[2 M + H]+的收率提高约为原始脂质的400-1000倍。此外，柠檬酸的质子化电离由于与磷脂的混合而受到抑制。这些结果表明磷脂与基质之间的基质效应有助于提高靶分子的灵敏度。因此，在双簇TOF - SIMS中，脂肪族羧酸与MALDI基质一样或更有效地增强磷脂的敏感性。
Matrix‐enhanced secondary ion mass spectrometry (ME‐SIMS) is an effective pre‐treatment method for the sensitivity enhancement of large molecules. Recently, matrix‐assisted laser desorption/ionization (MALDI) matrices, which consist of aromatic acids with benzene rings, have been developed using this technique. However, there are several differences in the desorption and ionization processes of SIMS and MALDI. In this study, the sensitivities of phospholipids mixed with aliphatic carboxylic acids were investigated using Bi‐cluster time‐of‐flight SIMS (TOF‐SIMS).Trans‐aconitic acid (tri‐carboxylic acid) and citric acid (hydroxycarboxylic acid) were used as the matrices. 2,5‐Dihydroxybenzoic acid (DHB), which is a typical aromatic MALDI matrix, was selected as the reference matrix. Whentrans‐aconitic acid and DHB were used as matrices, the secondary ion yields of [M + H]+and [2 M + H]+for phospholipids were approximately 10–150 times higher than that of the pristine lipid. For samples with citric acid, the yield enhancements of [M + H]+and [2 M + H]+were approximately 400–1000 times higher than those of pristine lipids. Furthermore, the protonated ionization of citric acid was mostly suppressed because of mixture with phospholipids. These results indicate that the matrix effect between phospholipids and the matrix contributes to the sensitivity enhancement of the target molecules. Hence, aliphatic carboxylic acid was equally or more effective than the MALDI matrix for the sensitivity enhancement of phospholipids in Bi‐cluster TOF‐SIMS.