BACKGROUND Recent technical advances in the extraction of dermal interstitial fluid (ISF) have stimulated interest in using this rather unexploited biofluid as an alternative to blood for detection and prediction of disease. However, knowledge about the presence of useful biomarkers for health monitoring in ISF is still limited. In this study, we characterized the lipidome of human suction blister fluid (SBF) as a surrogate for pure ISF and compared it to that of plasma. METHODS Plasma and SBF samples were obtained from 18 healthy human volunteers after an overnight fast. Total lipids were extracted and analyzed by liquid chromatography-tandem mass spectrometry. One hundred ninety-three lipid species covering 10 complex lipid classes were detected and quantified in both plasma and SBF using multiple reaction monitoring. A fraction of the lipid extract was subjected to alkaline transesterification and fatty acid methyl esters were analyzed by gas chromatography-mass spectrometry. RESULTS The total concentration of lipids in SBF was 17% of the plasma lipid concentration. The molar fraction of lipid species within lipid classes, as well as total fatty acids, showed a generally high correlation between plasma and SBF. However, SBF had larger fractions of lysophospholipids and diglycerides relative to plasma, and consequently less diacylphospholipids and triglycerides. Principal component analysis revealed that the interindividual variation in SBF lipid profiles was considerably larger than the within-subject variation between plasma and SBF. CONCLUSIONS Plasma and SBF lipid profiles show high correlation and SBF could be used interchangeably with blood for the analysis of major lipids used in health monitoring.

中文翻译：

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吸泡液的脂质分析：间质液和血浆中脂质的比较。

背景技术最近在提取真皮间质液（ISF）方面的技术进步激发了人们对使用这种尚未开发的生物流体作为血液的替代品来检测和预测疾病的兴趣。然而，对于 ISF 中是否存在用于健康监测的有用生物标志物的了解仍然有限。在这项研究中，我们将人吸泡液 (SBF) 的脂质组作为纯 ISF 的替代品进行了表征，并将其与血浆的脂质组进行了比较。方法 从 18 名健康志愿者禁食过夜后获取血浆和 SBF 样本。提取总脂质并通过液相色谱-串联质谱法进行分析。使用多反应监测在血浆和 SBF 中检测和量化了涵盖 10 个复杂脂质类别的 193 种脂质种类。对脂质提取物的一部分进行碱性酯交换反应，并通过气相色谱-质谱法分析脂肪酸甲酯。结果SBF中脂质总浓度为血浆脂质浓度的17%。脂质类别中脂质种类的摩尔分数以及总脂肪酸显示血浆和 SBF 之间普遍存在高度相关性。然而，相对于血浆，SBF 具有较大比例的溶血磷脂和甘油二酯，因此二酰基磷脂和甘油三酯较少。主成分分析显示，SBF 血脂谱的个体间差异远大于血浆和 SBF 之间的个体内差异。结论 血浆和 SBF 血脂谱显示出高度相关性，SBF 可以与血液互换使用，用于健康监测中主要血脂的分析。