Biophysical profiling of synthetic ultra-long tear film lipids

Tuomo Viitaja; Jan-Erik Raitanen; Jukka Moilanen; Riku O Paananen; Filip S Ekholm

doi:10.1016/j.colsurfb.2023.113145

Biophysical profiling of synthetic ultra-long tear film lipids

Colloids Surf B Biointerfaces. 2023 Mar:223:113145. doi: 10.1016/j.colsurfb.2023.113145. Epub 2023 Jan 14.

Authors

Tuomo Viitaja¹, Jan-Erik Raitanen², Jukka Moilanen³, Riku O Paananen⁴, Filip S Ekholm⁵

Affiliations

¹ Department of Chemistry, University of Helsinki, P.O. Box 55, FI-00014 Helsinki, Finland; Ophthalmology, University of Helsinki and Helsinki University Hospital, Haartmaninkatu 8, FI-00290 Helsinki, Finland.
² Department of Chemistry, University of Helsinki, P.O. Box 55, FI-00014 Helsinki, Finland.
³ Ophthalmology, University of Helsinki and Helsinki University Hospital, Haartmaninkatu 8, FI-00290 Helsinki, Finland.
⁴ Department of Chemistry, University of Helsinki, P.O. Box 55, FI-00014 Helsinki, Finland; Ophthalmology, University of Helsinki and Helsinki University Hospital, Haartmaninkatu 8, FI-00290 Helsinki, Finland. Electronic address: riku.o.paananen@gmail.com.
⁵ Department of Chemistry, University of Helsinki, P.O. Box 55, FI-00014 Helsinki, Finland. Electronic address: filip.ekholm@helsinki.fi.

PMID: 36701899
DOI: 10.1016/j.colsurfb.2023.113145

Abstract

The tear film lipid layer (TFLL) is a unique biological membrane of importance to the maintenance of ocular surface health. The underlying factors at play, e.g. the ability to retard evaporation and offer protection from the environment, are all closely connected to the properties of individual lipid components and their interplay. The TFLL contains unique ultra-long polar lipid species such as O-acyl-ω-hydroxy fatty acids, type I-St diesters and type II diesters, which are considered important for its proper function. Herein, we have synthesized model compounds from these categories and studied their biophysical and surface rheological properties at the aqueous interface. Altogether, we provide insights on the distinct biophysical profiles of these lipid classes and discuss how their interplay may affect the structure and function of the TFLL.

Keywords: Biophysics; Chemical synthesis; Langmuir monolayers; Structural elucidation; Tear film lipid layer lipids.

MeSH terms

Eye
Fatty Acids
Lipids* / chemistry
Surface Properties
Tears* / chemistry

Substances

Lipids
Fatty Acids