Chen R, Zhang N, Tseng A M, Li L
Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada.
Rapid Commun Mass Spectrom. 2000;14(23):2175-81. doi: 10.1002/1097-0231(20001215)14:23<2175::AID-RCM150>3.0.CO;2-2.
Matrix-assisted laser desorption/ionization (MALDI) mass spectrometry has the potential to become a valuable tool for the compositional analysis of copolymers. For a copolymer composed of structurally very similar building blocks with minor chain length changes, one would expect the relative peak intensities observed in the MALDI mass spectra to reflect its composition, at least within a narrow mass range. However, we show that variations in experimental conditions in MALDI can have a significant effect on the mass spectral appearance of a copolymer. The effects of concentration, laser power, type of matrices and solvents on mass spectra of an ethylene oxide/propylene oxide copolymer are illustrated. These somewhat surprising results show that great care needs to be exercised when interpreting copolymer spectra for compositional analysis, even for copolymers with structurally similar monomers. This work also points out that further studies are needed to better understand and optimize spectral acquisition conditions for reliable copolymer compositional analysis by MALDI.
基质辅助激光解吸/电离（MALDI）质谱法有潜力成为用于共聚物成分分析的重要工具。对于由结构非常相似的结构单元组成且链长变化较小的共聚物，人们预期在MALDI质谱中观察到的相对峰强度能反映其组成，至少在较窄的质量范围内是这样。然而，我们表明MALDI实验条件的变化会对共聚物的质谱外观产生显著影响。阐述了浓度、激光功率、基质类型和溶剂对环氧乙烷/环氧丙烷共聚物质谱的影响。这些有些令人惊讶的结果表明，即使对于具有结构相似单体的共聚物，在解释用于成分分析的共聚物光谱时也需要格外小心。这项工作还指出，需要进一步研究以更好地理解和优化光谱采集条件，以便通过MALDI进行可靠的共聚物成分分析。
