Structure of stratum corneum lipids characterized by FT-Raman spectroscopy and DSC. I. ceramides
| Autor: | Willi Rettig, Matthias Wegener, Siegfried Wartewig, Reinhard H.H. Neubert |
|---|---|
| Rok vydání: | 1996 |
| Předmět: |
chemistry.chemical_classification
Phase transition education.field_of_study Chemistry Population Analytical chemistry Pharmaceutical Science symbols.namesake Differential scanning calorimetry medicine.anatomical_structure Stratum corneum medicine symbols education Spectroscopy Raman spectroscopy Conformational isomerism Alkyl |
| Zdroj: | International Journal of Pharmaceutics. 128:203-213 |
| ISSN: | 0378-5173 |
| DOI: | 10.1016/0378-5173(95)04309-8 |
| Popis: | Fourier transform Raman spectroscopy and differential scanning calorimetry (DSC) were used to study ceramides type IV as a model substance for the ceramides fraction of stratum corneum lipids. The major part of the Raman spectrum consists of bands owing to the alkyl chain, but there are also bands which belong to the head group of the ceramides. The appearance of the conformationally dependent bands indicates the ordered structure of the hydrocarbon chains. The temperature dependence of the conformationally sensitive bands in the CH 2 stretching region (2800–2975 cm −1 ), in the chain C-C stretching region (1050–1150 cm −1 ), and in the low frequency region below 300 cm −1 is used to estimate the degree of order in terms of the relative population of trans and gauche conformers. The C-C stretching modes at 1063 cm −1 and 1130 cm −1 (trans conformation) and the asymmetric CH 2 stretching mode at 2880 cm −1 decrease rapidly near the phase transition temperature and disappear in the liquid state. The temperature and width of the phase transition, derived from Raman data, are similar to these of the DSC study. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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