Murphy Robert C, Leiker Thomas J, Barkley Robert M
Department of Pharmacology, University of Colorado, Denver, CO, USA.
Biochim Biophys Acta. 2011 Nov;1811(11):776-83. doi: 10.1016/j.bbalip.2011.06.019. Epub 2011 Jun 26.
Neutral lipids are a diverse family of hydrophobic biomolecules that have important roles in cellular biochemistry of all living species but have in common the property of charge neutrality. A large component of neutral lipids is the glycerolipids composed of triacylglycerols, diacylglycerols, and monoacylglycerols that can serve as cellular energy stores as well as signaling molecules. Another abundant lipid class in many cells is the cholesterol esters that are on one hand sterols and the other fatty acyl lipids, but in either case are neutral lipids involved in cholesterol homeostasis and transport in the blood. The analysis of these molecules in the context of lipidomics remains challenging because of their charge neutrality and the complex mixtures of molecular species present in cells. Various techniques have been used to ionize these neutral lipids prior to mass spectrometric analysis including electron ionization, atmospheric chemical ionization, electrospray ionization and matrix assisted laser desorption/ionization. Various approaches to deal with the complex mixture of molecular species have been developed including shotgun lipidomics and chromatographic-based separations such as gas chromatography, reversed phase liquid chromatography, and normal phase liquid chromatography. Several applications of these approaches are discussed. .
中性脂质是一类多样的疏水生物分子，在所有生物的细胞生物化学中都发挥着重要作用，其共同特性是电荷中性。中性脂质的一个主要成分是甘油脂质，由三酰甘油、二酰甘油和单酰甘油组成，它们既可以作为细胞能量储存物质，也可以作为信号分子。在许多细胞中，另一类丰富的脂质是胆固醇酯，一方面它属于甾醇类，另一方面属于脂肪酰脂质，但无论哪种情况，它们都是参与胆固醇体内平衡和血液运输的中性脂质。由于这些分子的电荷中性以及细胞中存在的复杂分子种类混合物，在脂质组学背景下对它们进行分析仍然具有挑战性。在质谱分析之前，已经使用了各种技术使这些中性脂质离子化，包括电子电离、大气压化学电离、电喷雾电离和基质辅助激光解吸/电离。已经开发了各种方法来处理复杂的分子种类混合物，包括鸟枪法脂质组学和基于色谱的分离方法，如气相色谱、反相液相色谱和正相液相色谱。本文讨论了这些方法的几种应用。
