Ion mobility spectrometry (IMS) has emerged as an important technology for the characterization of small molecules in biochemical and biological research. Here we present the METLIN-CCS Lipid Database, which includes collision cross section (CCS) values and IMS data for 750 unique lipid standards, many of which are not publicly available at present. Our database provides CCS values obtained by measuring each standard (in triplicate) in both positive and negative ionization modes, yielding seven different ion-types (for example, [M+H]⁺, [M+Na]⁺, [M−H]⁻, [M+NH₄]⁺, [M+H−H₂O]⁺, [M+Cl]^- and [M+HCOO]⁻). The 2413 measured lipid CCS values in the METLIN-CCS Lipid Database expand current IMS lipid database information^1,2,3,4 by adding experimental CCS values for new lipid standards and enabling the assessment of different ion types and adduction characteristics. Unlike other lipid databases that are generated from lipid extracts, the METLIN-CCS Lipid Database provides a unique resource created solely from standards, enabling more confident lipid identifications on- and off-tissue and new data for machine learning purposes.

METLIN was introduced in 2005 to provide experimental data^5,6,7 to help decipher small molecule structures. METLIN currently hosts experimental MS/MS and neutral loss data on over 930,000 molecular standards^6,7; however orthogonal analytical data such as CCS values are becoming increasingly important for confident identifications^8,9. Lipids, with their diversity in structure and function, are vital components of cell membranes, cellular functions and signalling processes¹⁰. Notably, CCS values do present a unique alternative to MS, allowing for the separation and characterization and/or identification of isomeric lipid species (for example, in Fig. 1, phosphatidylcholine (PC) 36:2 and phosphatidylethanolamine (PE) 39:2 both have a mass of 785.5935 Da).

离子迁移谱 (IMS) 已成为生化和生物学研究中小分子表征的重要技术。在这里，我们介绍 METLIN-CCS 脂质数据库，其中包括 750 种独特脂质标准品的碰撞截面 (CCS) 值和 IMS 数据，其中许多标准目前尚未公开。我们的数据库提供了通过在正电离模式和负电离模式下测量每个标准品（一式三份）获得的 CCS 值，产生七种不同的离子类型（例如，[M+H] ⁺ 、[M+Na] ⁺ 、[M−H ] ^- 、[M+NH ₄ ] ⁺ 、[M+H−H ₂ O] ⁺ 、[M+Cl] ^-和[M+HCOO] ^- ）。 METLIN-CCS 脂质数据库中的 2413 个测量脂质 CCS 值通过添加新脂质标准的实验 CCS 值并能够评估不同离子类型和内合特性，扩展了当前 IMS 脂质数据库信息^1,2,3,4。与从脂质提取物生成的其他脂质数据库不同，METLIN-CCS 脂质数据库提供了仅根据标准创建的独特资源，可以更可靠地识别组织内和组织外的脂质以及用于机器学习目的的新数据。

METLIN 于 2005 年推出，提供实验数据^5,6,7来帮助破译小分子结构。 METLIN 目前托管超过 930,000 个分子标准品的实验 MS/MS 和中性损失数据^6,7 ；然而，CCS 值等正交分析数据对于可靠的识别变得越来越重要^8,9 。脂质具有结构和功能的多样性，是细胞膜、细胞功能和信号传导过程的重要组成部分¹⁰ 。值得注意的是，CCS 值确实提供了 MS 的独特替代方案，允许分离、表征和/或鉴定异构脂质种类（例如，图 1 中的磷脂酰胆碱 (PC) 36:2 和磷脂酰乙醇胺 (PE) 39:2）两者的质量均为 785.5935 Da）。