Department of Chemistry, Humboldt University Berlin, Berlin, Germany.
Mass Spectrom Rev. 2023 Jan;42(1):144-188. doi: 10.1002/mas.21716. Epub 2021 Jul 22.
Lignin is currently one of the most promising biologically derived resources, due to its abundance and application in biofuels, materials and conversion to value aromatic chemicals. The need to better characterize and understand this complex biopolymer has led to the development of many different analytical approaches, several of which involve mass spectrometry and subsequent data analysis. This review surveys the most important analytical methods for lignin involving mass spectrometry, first looking at methods involving gas chromatography, liquid chromatography and then continuing with more contemporary methods such as matrix assisted laser desorption ionization and time-of-flight-secondary ion mass spectrometry. Following that will be techniques that directly ionize lignin mixtures-without chromatographic separation-using softer atmospheric ionization techniques that leave the lignin oligomers intact. Finally, ultra-high resolution mass analyzers such as FT-ICR have enabled lignin analysis without major sample preparation and chromatography steps. Concurrent with an increase in the resolution of mass spectrometers, there have been a wealth of complementary data analyses and visualization methods that have allowed researchers to probe deeper into the "lignome" than ever before. These approaches extract trends such as compound series and even important analytical information about lignin substructures without performing lignin degradation either chemically or during MS analysis. These innovative methods are paving the way for a more comprehensive understanding of this important biopolymer, as we seek more sustainable solutions for our human species' energy and materials needs.
木质素目前是最有前途的生物来源资源之一，因为它丰富且可应用于生物燃料、材料，并可转化为有价值的芳香族化学品。需要更好地对这种复杂的生物聚合物进行特性描述和理解，这导致了许多不同的分析方法的发展，其中有一些涉及质谱分析和随后的数据分析。本文综述了涉及质谱分析的木质素的最重要的分析方法，首先介绍了涉及气相色谱、液相色谱的方法，然后继续介绍了更现代的方法，如基质辅助激光解吸电离和飞行时间二次离子质谱。接下来是直接对木质素混合物进行离子化的技术，而无需色谱分离，使用较软的大气离子化技术，使木质素低聚物保持完整。最后，超高速分辨率质谱仪，如傅里叶变换离子回旋共振（FT-ICR），无需进行主要的样品制备和色谱分离步骤即可进行木质素分析。随着质谱仪分辨率的提高，出现了大量的补充数据分析和可视化方法，使研究人员能够以前所未有的深度探测“木质素组”。这些方法提取出化合物系列等趋势，甚至在不进行木质素降解的情况下，在化学或 MS 分析过程中，都能获得有关木质素亚结构的重要分析信息。这些创新方法为更全面地理解这种重要的生物聚合物铺平了道路，因为我们正在为人类的能源和材料需求寻找更可持续的解决方案。
