小鼠大腦中脂質體學分析的液相層析條件研究

Abstract

塑膠的壽命極長，在物理、化學或生物作用下很容易降解為較小的微塑膠 (Microplastics, MPs)。MPs對哺乳動物的潛在毒性仍有爭議。本研究應用液相層析-質譜聯用(LC-MS)技術，進行毒性相關差異脂質的非靶向(Untargeted)分析。我們使用脂質體學分析平台，結合C18、T3和C8三種層析管柱，並搭配甲酸、乙酸、甲酸銨與乙酸銨四種添加劑，設計12種層析條件。結果顯示，在正電模式下C18管柱可有效分離碳鏈較長的脂質，提供最佳的檢測能力。而在負電模式下，T3管柱能有效滯留具極性頭基的脂質，進一步提升鑑定能力。綜合評估後，正電模式使用C18管柱搭配甲酸銨與甲酸，負電模式使用T3管柱搭配乙酸銨與乙酸，兩者結合可顯著提升脂質的覆蓋率，從而能夠鑑定多達583種脂質。隨後，此優化的脂質體學平台被應用於研究小鼠大腦接觸微塑膠後脂質體學的變化，為塑膠微粒引起的潛在毒性提供新的見解。Plastics have an extremely long lifespan and can readily degrade into smaller microplastics (MPs) under physical, chemical or biological forces. The potential toxicity of MPs to mammals remains controversial. In this study, liquid chromatography–mass spectrometry (LC-MS) was applied for untargeted lipidomic analysis of toxicity-related lipids. A lipidomics analytical platform was developed, combining three chromatographic columns (C18, T3, and C8) and four additives (formic acid, acetic acid, ammonium formate, and ammonium acetate) to design 12 chromatographic conditions. The results showed that in positive ion mode, the C18 column effectively separated lipids with longer carbon chains, providing the best detection performance. In negative ion mode, the T3 column effectively retained lipids with polar head groups, enhancing lipid identification capacity. Our results indicate that combining the C18 column with ammonium formate and formic acid for positive ion mode and the T3 column with ammonium acetate and acetic acid for negative ion mode showed significant complementarity, can significantly improve the lipid coverage, enabling the identification of up to 583 lipid species. This optimized lipidomics platform was subsequently applied to investigate lipidomic alterations in the mouse brain following microplastic exposure, providing new insights into the potential toxicity induced by MPs.