树脂化石复杂化学成分解析的前处理方法研究进展

A Review on Pretreatment Method for the Analysis of Complex Chemical Composition of Resinite

  • 摘要: 树脂化石复杂有机组分的分离检测及解析一直是树脂化石研究中的热点和难点,早期前处理方法和一维气相色谱-质谱的分离分析效率有限,挥发性组分数据易丢失,峰重叠现象严重,很难对其化学组成进行准确鉴定。本文对比分析了4种前处理方法(溶剂萃取、化学衍生化、热裂解和固相微萃取)在树脂化石前处理中的适用范围和优缺点。(1)溶剂萃取法适用于分析树脂化石中倍半萜类、三萜类、酚类、饱和烃、芳烃等物质,但石化程度高的琥珀所需溶解时间长且不能完全溶解,不适用此方法,石化程度低的柯巴树脂更适用于此方法。(2)化学衍生化法适用于定性分析基团中有活泼氢的分子,衍生化后可有效改善相关分子的挥发性、稳定性和增强响应信号强度。(3)热裂解法主要针对树脂化石有机聚合物的主要骨架,但是以裂解碎片还原初始结构会存在一定偏差。(4)固相微萃取法适用于树脂化石中的挥发份/半挥发份的分析,但易出现检出物不完全的情况。结合顶空高容量固相萃取法和直接热脱附法样品前处理技术和全二维气相色谱-质谱技术,可检测到传统分析方法3~4倍的化合物种类数量, 并通过非靶向代谢组学策略分析不同产地树脂化石色谱质谱结果,可筛查出更具代表性的特征化学信息,研究复杂有机组分的分离、同分异构物的准确判别,解决固相复杂有机组分检测解析的突出难题,在挥发性-半挥发性有机组分分离及二次富集、高特异性生物标志物筛选方面高效解析,为树脂化石在其古生态环境复原及成熟演化过程探究奠定理论和技术基础。

     

    Abstract: The separation, detection, and analysis of complex organic compositions in fossil resin have always been a hot and difficult point in the research. The early sample pretreatment methods and the separation and analysis efficiency of one-dimensional gas chromatography-mass spectrometry (1D GC-MS) were limited, overlapping spectral peaks and missing mass spectra peaks of trace substances easily occurred in the chromatography-mass spectrometry analysis, .Hence, it was difficult to accurately identify its chemical compositions. In this review, it systematically summarizes the application, advantages, and disadvantages of four pretreatment methods (solvent extraction, chemical derivatization, pyrolysis, and solid phase microextraction) used in the compositions analysis of resinites. (1)Solvent extraction is suitable for the analysis of sesquiterpenes, triterpenes, phenols, saturated hydrocarbons, aromatic hydrocarbons, and other substances in the resin fossils. However, amber with high degree of petrifaction requires a long time to dissolve and cannot be completely dissolved, hence, solvent extraction is much more applicable to copal with lower degree rather than highly fossilized amber. (2)Chemical derivatization is applicable to qualitative analysis of molecules with active hydrogen in the group, which can effectively improve the volatility and stability of related molecules and enhance the response signal intensity after derivatization. (3)Thermal pyrolysis mainly aims at the analysis of the main macromolecular skeleton of the resinite, but there will be some deviation in the reduction of the initial structure by the pyrolysates. (4)Solid phase microextraction is suitable for the analysis of volatile/semi-volatile components in amber, but it is prone to incomplete detection. The sample pretreatment technologies of headspace high-capacity solid phase microextraction and direct thermal desorption combining with comprehensive two-dimensional gas chromatography and mass spectrometry (GC-MS) were creatively proposed, which could detect 3-4 times as many compounds number as the traditional analysis method. More representative biomarkers can be screened by untargeted metabolomics strategies to analyze the GC-MS results of resinites from different habitats. Our team will focus on the isolation of complex organic components and the accurate identification of isomers, and reveal the origin of ancient plants and genesis of resin fossils of different origins and ages. It is expected to solve the outstanding problems in the detection and analysis of complex organic components in the solid phase, and efficiently analyze volatile and semi volatile organic compounds in terms of separation, secondary enrichment, and screening of highly specific biomarkers, which provides a theoretical and technical foundation for the exploration of reconstruction of their palaeoecological environment and maturation evolution.

     

/

返回文章
返回