实时质谱新技术分析南极磷虾油的脂质组学轮廓

Novel Real-time Mass Spectrometry for Detecting the Lipidomics Profile of Antarctic Krill Oil

快速蒸发离子化质谱(REIMS)是近几年发展的一种无需任何样品前处理的新型原位电离质谱。基于REIMS建立南极磷虾油脂质组学轮廓的实时检测方法。将南极磷虾冷冻干燥后采用95%乙醇提取虾油,通过加热探头(500℃)离子化,形成气溶胶由文丘里泵氮气(2 bar)驱动并引入质谱,与端口处内设铬铝钴耐热钢A1灯丝(1.1Ω,3 V)碰撞发生二次电离。以丙二醇/亮氨酸脑啡肽混合物为辅助溶剂,经针泵注射进样器以0.1 mL/min的流量引入端口,用于清洗杂质,提高信号强度,锁定质量校正。结果显示,南极磷虾脂质分子离子峰主要出现在m/z 200~900区域范围内,并由脂肪酸和磷脂2个明显的峰簇组成。经结构鉴定和相对含量测定,共计20种脂肪酸和26种磷脂分子被检出,其中EPA(m/z 301,21.59%)和DHA(m/z 327,14.44%)为主要脂肪酸离子;[PG 36:7-H]-(m/z 763,11.67%)和[PC O-38:3-choline]-/[PE O-38:3-NH3]-(m/z 737,11.46%)为主要磷脂离子。经方法学验证,该REIMS高通量实时检测方法灵敏度和精密度均能满足南极磷虾油中脂肪酸和磷脂的脂质组学轮廓分析测试要求。REIMS法实时检测南极磷虾油脂质组学轮廓具有快速、高效的优点,相关数据能为质谱工作者提供理论基础,为海洋功能食品企业和部门提供相关依据和参考。

Rapid evaporative ionization mass spectrometry(REIMS)is a recently developed ambient mass spectrometric technique without any sample preparation.In this study,a real-time lipidomics detection method was developed for fast profiling of Antarctic krill oil on the basis of REIMS.The Antarctic krill oil was extracted using 95%ethanol from freeze dried Antarctic krill.The compounds inside were evaporated by a heating probe at 500℃,and the aerosol generated was transferred into the interface of mass spectrometer by a Venturi pump with nitrogen at 2 bar.In the interface,a coil of Kanthal A1 wire(1.1Ω,3 V)was set for ion collision.A syringe pump was used to inject the matrix solvent at a flow rate of 0.1 mL/min throughout experiments.The propan-2-ol,together with the aerosol,entered the mass spectrometer via a stainless steel MS inlet capillary.The results showed that the lipid ion peaks were generally produced in the m/z range of 200-900.There are generally two clusters,including the cluster of fatty acid ions at m/z 200-500 and the cluster of phospholipid ions at m/z 600-900.After statistic analysis and lipid identification,a total of 20 fatty acid molecular species and 26 phospholipid molecular species were found.[EPA-H]-(m/z,21.59%)and[DHA-H]-(m/z 327,14.44%)were the most abundant fatty acid ions,while[PG 36:7-H]-(m/z 763,11.67%)and[PC O-38:3-choline]-/[PE O-38:3-NH3]-(m/z 737,11.46%)were the major phospholipid ions.After method validation,it indicated that the proposed REIMS method was sensitive and precise for high-throughput lipidomics profiling of Antarctic krill oil,which could provide important theoretical basis for mass spectrometry workers and technical support for related enterprise and functional departments.