Cody Robert B, Fouquet Thierry
JEOL USA Inc., 11 Dearborn Rd., Peabody, MA 01960, USA.
Research Institute for Sustainable Chemistry, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Japan.
Anal Chim Acta. 2017 Oct 9;989:38-44. doi: 10.1016/j.aca.2017.08.005. Epub 2017 Aug 13.
Paper spray ionization coupled with a high-resolution time-of-flight mass spectrometer was applied to the analysis of 13 block and 2 random ethylene oxide/propylene oxide (EO/PO) copolymers as well as to standard samples of poly(ethylene oxide) and poly(propylene oxide) homopolymers. Paper spray mass spectra could be obtained rapidly and, unlike electrospray ionization, were not subject to contamination and sample carryover. For comparison, polyether samples were also measured on a MALDI/TOF system with ultrahigh mass resolving power. MALDI/high-resolution time-of-flight mass spectrometry exhibited single-charge ions characteristic of the polymer distributions whereas the paper spray mass spectra exhibited charge states ranging from one to six charges. Kendrick mass defect plots of the multiple-charge ions in the paper spray mass spectra exhibit isotopic splitting of the Kendrick mass defects, facilitating visualization of the number of charges in each series. The slope of the KMD plots can be used to estimate the percentage of ethylene oxide in the copolymers. In-source fragmentation permitted the distinction between block and random copolymers.
纸喷雾电离与高分辨率飞行时间质谱联用,用于分析13种嵌段和2种无规环氧乙烷/环氧丙烷(EO/PO)共聚物以及聚环氧乙烷和聚环氧丙烷均聚物的标准样品。可以快速获得纸喷雾质谱,并且与电喷雾电离不同,它不会受到污染和样品残留的影响。为了进行比较,还在具有超高质量分辨能力的基质辅助激光解吸电离/飞行时间(MALDI/TOF)系统上对聚醚样品进行了测量。MALDI/高分辨率飞行时间质谱显示出聚合物分布的单电荷离子特征,而纸喷雾质谱显示出从一到六个电荷的电荷状态。纸喷雾质谱中多电荷离子的肯德里克质量亏损图显示了肯德里克质量亏损的同位素分裂,便于直观显示每个系列中的电荷数。KMD图的斜率可用于估算共聚物中环氧乙烷的百分比。源内碎裂允许区分嵌段共聚物和无规共聚物。