Engler Martin S, Crotty Sarah, Barthel Markus J, Pietsch Christian, Schubert Ulrich S, Böcker Sebastian
Chair of Bioinformatics, Friedrich Schiller University Jena, Ernst-Abbe-Platz 2, 07743, Jena, Germany.
Laboratory of Organic and Macromolecular Chemistry (IOMC), Friedrich Schiller University Jena, Humboldstr. 10, 07743, Jena, Germany.
Rapid Commun Mass Spectrom. 2016 May 30;30(10):1233-1241. doi: 10.1002/rcm.7553.
Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) is frequently used to analyze homo- and copolymers, i.e. for computing copolymer fingerprints. However, the oligomer abundances are influenced by mass discrimination, i.e. mass- and composition-dependent ionization. We have developed a computational method to correct the abundance bias caused by the mass discrimination.
MALDI-TOFMS in combination with computational methods was used to investigate three random copolymers with different ratios of styrene and isoprene. Furthermore, equimolar high- and low-mass styrene and isoprene homopolymers (2500 and 4200 Da) were mixed and also analyzed by MALDI-TOFMS. The abundances of both copolymers and homopolymers were corrected for mass discrimination effects with our new method.
The novel computational method was integrated into the existing COCONUT software. The method was demonstrated using the measured styrene and isoprene co- and homopolymers. First, the method was applied to homopolymer spectra. Subsequently, the copolymer fingerprint was computed from the copolymer MALDI mass spectra and the correcting function applied. The changes in the composition are plausible, indicating that correction of copolymer abundances was reasonable.
Our computational method may help to avoid erroneous conclusions when analyzing copolymer MS spectra. The software is freely available and represents a step towards comprehensive computational support in polymer science. Copyright © 2016 John Wiley & Sons, Ltd.
基质辅助激光解吸/电离飞行时间质谱法（MALDI-TOFMS）常用于分析均聚物和共聚物，即用于计算共聚物指纹图谱。然而，低聚物丰度受质量歧视影响，即受质量和组成依赖性电离影响。我们开发了一种计算方法来校正由质量歧视引起的丰度偏差。
将MALDI-TOFMS与计算方法相结合，用于研究三种具有不同苯乙烯和异戊二烯比例的无规共聚物。此外，将等摩尔的高质量和低质量苯乙烯及异戊二烯均聚物（2500和4200 Da）混合，并通过MALDI-TOFMS进行分析。使用我们的新方法校正了共聚物和均聚物的丰度，以消除质量歧视效应。
这种新颖的计算方法已集成到现有的COCONUT软件中。使用测得的苯乙烯和异戊二烯共聚物及均聚物对该方法进行了验证。首先，将该方法应用于均聚物光谱。随后，根据共聚物MALDI质谱计算共聚物指纹图谱，并应用校正函数。组成变化合理，表明共聚物丰度的校正是合理的。
我们的计算方法可能有助于在分析共聚物质谱图时避免得出错误结论。该软件可免费获取，代表了聚合物科学向全面计算支持迈出的一步。版权所有© 2016约翰威立父子有限公司。
