| Popis: |
The biological membranes are multicomponent systems with two compositionally specific leaflets. Due to the extremely complex structure, their characterization is often performed on simpler models, which are dominated by membranes made only of lipids, such as sphingomyelin (SM). [1] With the main phase transition temperatures in the range of 30- 45 °C, depending on the length of hydrophobic chains, SM might have the potential to introduce lateral heterogeneity and immutability in the membrane plane. The role of SM in biomembranes is believed to participate in the formation of a phase domain structure, although there is no agreement about the molecular basis of this domain structure. Since they possess several hydrogen bond-accepting and -donating groups at the polar/non-polar interface, hydrogen bonding seems particularly likely in the case of sphingomyelin. Using the brain SM, which is a mixture of SM lipids with different lengths of hydrophobic chains, we examined the effect of buffers of different pH values on hydrogen bond network with calorimetric and spectroscopic techniques. The analysis of the brain SM multilamellar liposomes with FTIR ATR and fluorescence spectroscopy, UV/Vis spectrophotometry and DSC calorimetry will try to clarify influence of different pH on SM structural domains. |
