Ling Ling, Li Ying, Wang Sheng, Guo Liming, Xiao Chunsheng, Chen Xuesi, Guo Xinhua
State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130012, China.
Key Laboratory of Polymer Ecomaterials, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022, China.
J Am Soc Mass Spectrom. 2018 Apr;29(4):704-710. doi: 10.1007/s13361-017-1881-y. Epub 2018 Jan 18.
Matrix interference ions in low mass range has always been a concern when using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) to analyze small molecules (<500 Da). In this work, a novel matrix, N1,N4-dibenzylidenebenzene-1,4-diamine (DBDA) was synthesized for the analyses of small molecules by negative ion MALDI-TOF MS. Notably, only neat ions ([M-H]) of fatty acids without matrix interference appeared in the mass spectra and the limit of detection (LOD) reached 0.3 fmol. DBDA also has great performance towards other small molecules such as amino acids, peptides, and nucleotide. Furthermore, with this novel matrix, the free fatty acids in serum were quantitatively analyzed based on the correlation curves with correlation coefficient of 0.99. In addition, UV-Vis experiments and molecular orbital calculations were performed to explore mechanism about DBDA used as matrix in the negative ion mode. The present work shows that the DBDA matrix is a highly sensitive matrix with few interference ions for analysis of small molecules. Meanwhile, DBDA is able to precisely quantify the fatty acids in real biological samples. Graphical Abstract ᅟ.
在使用基质辅助激光解吸/电离飞行时间质谱（MALDI-TOF MS）分析小分子（<500 Da）时，低质量范围内的基质干扰离子一直是一个问题。在这项工作中，合成了一种新型基质N1,N4-二亚苄基苯-1,4-二胺（DBDA），用于通过负离子MALDI-TOF MS分析小分子。值得注意的是，质谱图中仅出现了无基质干扰的脂肪酸纯离子（[M-H]），检测限（LOD）达到0.3 fmol。DBDA对其他小分子如氨基酸、肽和核苷酸也有很好的性能。此外，使用这种新型基质，基于相关系数为0.99的相关曲线对血清中的游离脂肪酸进行了定量分析。此外，进行了紫外-可见实验和分子轨道计算，以探索DBDA在负离子模式下用作基质的机制。目前的工作表明，DBDA基质是一种用于分析小分子的高灵敏度基质，干扰离子很少。同时，DBDA能够精确地定量实际生物样品中的脂肪酸。图形摘要ᅟ。
