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Phenol Red Thread-based Sampling Procedure for Untargeted Tear Fluid Lipidomics in Biomarker Discovery
Published on: December 12, 2025
Human tear fluid lipidome: from composition to function
Antti H Rantamäki1, Tuulikki Seppänen-Laakso, Matej Oresic
1Helsinki Eye Lab, Department of Ophthalmology, University of Helsinki, Helsinki, Finland.
Plos One
|May 17, 2011
Summary
Human tear fluid contains essential polar lipids for proper non-polar lipid spreading. This study identifies major lipids and their physiological role in ocular surface health.
Area of Science:
- Ophthalmology
- Biochemistry
- Lipidomics
Background:
- The lipid composition of human aqueous tear fluid is crucial for ocular surface health.
- Understanding the tear fluid lipidome is essential for diagnosing and treating ocular surface diseases.
Purpose of the Study:
- To identify the major lipids in human aqueous tear fluid.
- To elucidate the physiological significance of the tear fluid lipidome.
- To investigate the role of polar lipids in non-polar lipid spreading.
Main Methods:
- Thin-layer chromatography
- Enzymatic analysis
- Mass spectrometry (UPLC-QTOF-MS)
- Macroscopic spreading experiments at air-water interface
Main Results:
- Choline-containing lipids (48±14 µM), triglycerides (10±0 µM), and cholesteryl esters (21±18 µM) were quantified enzymatically.
- Phosphatidylcholine and phosphatidylethanolamine were the most abundant polar lipids (88±6%).
- Triglycerides were the only non-polar lipids detected by mass spectrometry; cholesteryl and wax esters were absent.
- Spreading experiments demonstrated that polar lipids are necessary for non-polar lipid spreading.
Conclusions:
- Polar lipids are the predominant lipid species in human tear fluid.
- The identified lipid composition has a physiological rationale related to tear film function.
- These findings offer insights into the functional role of tear fluid lipids and potential therapeutic targets for ocular surface diseases.
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