导电聚合物喷雾电离质谱法对微量全血代谢轮廓即时监测

Instant Monitoring of Metabolomic Profile for Trace of Whole Blood Using Conductive Polymer Spray Ionization Mass Spectrometry

血液代谢物水平可用于术后生理代谢状况的个体化精准评估,这对体液整体代谢轮廓的即时检验提出了迫切的技术需求。该文介绍了导电聚合物喷雾电离质谱(CPSI-MS)在体液代谢物多重监测中的应用价值。该技术采用由碳纳米管(CNT)和聚甲基丙烯酸甲酯(PMMA)组成的导电聚合物作为血液加载与原位电离喷头。当对该聚合物施加4.5 kV的直流电压后,喷头尖端的萃取溶剂液滴(甲醇-水,体积比1∶1,5μL)在高压驱动下形成带电荷喷雾,将从1μL稀释干血点中萃取解吸的内源性成分进行直接质谱检测。该方法覆盖了600多种内源性代谢物和脂质,涉及20多条代谢通路,包括能量代谢、氨基酸代谢、核苷酸代谢和脂质代谢等。该研究还将经肝大部切除手术的代谢C57BL/6小鼠选为模型对象,采集术后不同时间点的微量血液样本加载于导电聚合物喷头形成干血点样本,监测了数百种代谢物变化来精确表征个体的生理恢复差异。最终发现了分布于三羧酸循环、精氨酸代谢、甘油脂代谢、甘油磷酸胆碱代谢的一组代谢标志物群,从而为肝切除术后生理代谢功能恢复的分子评价提供了依据。

The blood's metabolism could be used to provide a precise evaluation on the post-surgery physiological status,which poses an urgent technical demand for a point-of-care test for global metabolomic profiling.Therefore,the practical value of conductive polymer spray ionization mass spectrometry(CPSI-MS)in the multiplex monitoring of endogenous metabolites in a trace volume of whole blood was presented in this paper.The fabricated conductive polymer was composed of carbon nanotube(CNT)and polymethyl methacrylate(PMMA).After applying a high voltage of 4.5 kV for generating charged droplet spray,trace volume of extraction solvent(methanol-H2O,1∶1,5μL)was enough to extract,desorb and ionize over 600 endogenous metabolites and lipids in the only 1μL of diluted dried blood spot deposited on the tip,covering more than 20 fundamental metabolism pathways including the energy metabolism,amino acids metabolism,nucleotides metabolism,and lipids metabolism,etc.To give a proof-of-concept illustration,the C57BL/6 mice experiencing the hepatectomy were selected as the model objects.The individual differences in physiological recovery were precisely characterized by capturing hundreds of metabolites changes with a period of 48 h.Finally,a panel of metabolites mainly in the Krebs cycle,arginine metabolism,glycerolipids metabolism,and glycerophosphorylcholine metabolism could give a prognostic reference for the functional recovery of the mice from the hepatectomy.