Raman Spectroscopic Investigations on Binary Lipid Mixtures
Abstract Raman spectra in the C‐H and C‐C stretching vibration region for dipalmitoyl‐phosphatidic acid and mixtures of dimyristoyl‐, dipalmitoyl‐ and distearoyl lecithin are reported. Suitable peak height ratios show characteristic changes with temperature. From the data of the pure lipids one can...
| Published in: | Berichte der Bunsengesellschaft für physikalische Chemie |
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| Main Author: | |
| Format: | Article in Journal/Newspaper |
| Language: | English |
| Published: |
Wiley
1978
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| Subjects: | |
| Online Access: | http://dx.doi.org/10.1002/bbpc.19780820939 https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1002%2Fbbpc.19780820939 https://onlinelibrary.wiley.com/doi/pdf/10.1002/bbpc.19780820939 |
| Summary: | Abstract Raman spectra in the C‐H and C‐C stretching vibration region for dipalmitoyl‐phosphatidic acid and mixtures of dimyristoyl‐, dipalmitoyl‐ and distearoyl lecithin are reported. Suitable peak height ratios show characteristic changes with temperature. From the data of the pure lipids one can derive ordered‐fluid transition temperatures that are in good agreement with the values from other methods: 57°C for DPPA at p H 9, 23.5°C for DML, 42°C for DPL and 55°C for DSL. – For the DML/DPL mixture a somewhat broadened transition at intermediate temperature is found (33.5°C for DML: DPL = 1:1). – For a mixture of DPPA and polylysine‐bound DPPA two distinct transition temperatures can be seen, which reflect the immiscibility of the two components. – For mixtures of DML and DSL more complicated transition curves are found. The peak height ratios of C – H vibrations at 2880 and 2850 cm −1 nevertheless can be used to construct a phase diagram. The transition curve of C‐C stretching vibrations at 1130 and 1100 cm −1 seems to monitor a complex phase separation behaviour which cannot be explained for the moment in full detail without additional experimental results. |
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