| Autor: |
Stubb H; Department of Chemistry, University of Helsinki, P.O. Box 55, FI-00014 Helsinki, Finland., Viitaja T; 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., Trevorah RM; Department of Physics, University of Helsinki, P.O. Box 64, FI-00014 Helsinki, Finland., Raitanen JE; Department of Chemistry, University of Helsinki, P.O. Box 55, FI-00014 Helsinki, Finland., Moilanen J; Ophthalmology, University of Helsinki and Helsinki University Hospital, Haartmaninkatu 8, FI-00290 Helsinki, Finland., Svedström KJ; Department of Physics, University of Helsinki, P.O. Box 64, FI-00014 Helsinki, Finland., Ekholm FS; Department of Chemistry, University of Helsinki, P.O. Box 55, FI-00014 Helsinki, Finland. |
| Abstrakt: |
The tear film lipid layer (TFLL) plays a vital part in maintenance of ocular health and represents a unique biological barrier comprising unusual and specialized lipid classes and species. The wax and cholesteryl esters (WEs and CEs) constitute roughly 80-90% of the TFLL. The majority of species in these lipid classes are branched and it is therefore surprising that the synthesis and properties of the second largest category of species, i.e., the anteiso -branched species, remain poorly characterized. In this study, we have developed a total synthesis route and completed a detailed NMR spectroscopic characterization of two common anteiso -branched species, namely: (22 S )-22-methyltetracosanyl oleate and cholesteryl (22' S )-22'-methyltetracosanoate. In addition, we have studied their structural properties in the bulk state by wide-angle and small-angle X-ray scattering and their behavior at the aqueous interface using Langmuir monolayer techniques. A comparison to the properties displayed by iso -branched and straight-chain analogues indicate that branching patterns lead to distinct properties in the CE and WE lipid classes. Overall, this study complements the previous work in the field and adds another important brick in the tear film insights wall. |
