黄土-古土壤序列脂肪酸的 LC-MS/MS 检测法的建立及其在北京东灵山的应用

doi:10.7523/j.ucas.2026.004

摘要/Abstract

摘要： 本研究建立了一种液相色谱-串联质谱（LC-MS/MS）高灵敏度的方法,用于全新世黄土-古土壤序列中游离脂肪酸（C₁₀ - C₃₂）的定量分析。通过对样品制备（超声提取、硅胶柱纯化）、色谱分离、质谱参数（MRM 模式）的系统优化,对 36 种脂肪酸进行了高效的分离和定量。该方法检出限低（0.5 - 15.64 ng/mL）,精密度高（RSD < 1%）。将该方法应用于北京东灵山全新世剖面,首次成功鉴定并定量了该地层中 C_14:1、C_15:1、C_17:1等几种单不饱和脂肪酸。这些短链单不饱和脂肪酸通常源于微生物活动,其含量的变化可能直接响应于土壤湿度与温度的变化。结合磁化率和粒度指标,系统揭示了脂肪酸组成的垂直变化规律,对古气候重建具有重要意义。结果表明,2965 - 528 cal yr BP 是东灵山全新世最温暖、最湿润的时期。本研究不仅填补了 LC-MS/MS 分析黄土脂肪酸的方法学空白,而且为高分辨率古环境重建提供了新的生物标志物指标和技术支持。

关键词: 液相色谱质谱联用, 脂肪酸, 黄土-古土壤序列, 古环境重建, 东灵山

Abstract: This study developed a highly sensitive method based on liquid chromatography-tandem mass spectrometry (LC-MS/MS) for the quantitative analysis of free fatty acids (C₁₀ - C₃₂) in Holocene loess-paleosol sequences. Through systematic optimization of sample preparation (ultrasonic extraction and silica gel column purification), chromatographic separation, and mass spectrometric parameters (MRM mode), 36 fatty acids were efficiently separated and quantified. The method demonstrated low detection limits (0.5 - 15.64 ng/mL) and excellent precision (RSD < 1%). Applied to a Holocene profile from Donglingshan, Beijing, the method successfully identified and quantified several monounsaturated fatty acids (e.g., C_14:1, C_15:1, C_17:1) for the first time in such strata. These short-chain monounsaturated fatty acids typically originate from microbial activity, and changes in their content may directly respond to variations in soil moisture and temperature. Integrating magnetic susceptibility and grain-size data, the vertical variations in fatty acid composition were systematically revealed, indicating their significance for paleoclimate reconstruction. The results suggest that the period from 2965 to 528 cal yr BP was the warmest and most humid of the Holocene at Donglingshan. This research not only fills a methodological gap in LC-MS/MS analysis of loess fatty acids but also provides a new biomarker indicator and technical support for high-resolution paleoenvironmental reconstruction.

Key words: LC-MS/MS, Fatty acids, Loess-paleosol sequence, Paleoenvironmental reconstruction, Donglingshan

中图分类号:

P593

龙雨佳, 李玉梅. 黄土-古土壤序列脂肪酸的 LC-MS/MS 检测法的建立及其在北京东灵山的应用[J]. 中国科学院大学学报, DOI: 10.7523/j.ucas.2026.004.

LONG Yujia, LI Yumei. Development and Application of an LC-MS/MS Method for the Analysis of Fatty Acids in a Loess-Paleosol Sequence from Donglingshan, Beijing^*[J]. Journal of University of Chinese Academy of Sciences, DOI: 10.7523/j.ucas.2026.004.

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