Polymer-free and polymer-bearing liposomes from dimyristoylphosphatidylcholine (DMPC), dimyristoylphosphatidylglycerol (DMPG) and cholesterol (Ch) 10:1:1 (w/w/w) were pre- pared. Polymer-bearing liposomes were formed by incorporating an uncharged polymer [poly(vinyl alcohol) (PVA), poly(vinyl alcohol-co-vinylacetal) (PVA-Al), poly(vinyl alcohol-co-vinyl propional) (PVA-Prol) poly(vinyl alcohol-co-vinyl butiral) (PVA-Bul) copolymer, polyvinyl pyrrolidone (PVP) or polyethylene glycol (PEG) respectively]. The effect of some polymers on the phase transition parameter of phospholipids (DMPC and DMPG) has been studied by differential scanning calorimetry (DSC). DSC has become a standard technique for studying the thermally induced transition of phospholipid molecules from an ordered crystalline-like state at low temperature (gel phase) to a liquid crystalline-like state at higher temperature. The interaction between phospholipids and polymers was characterized by the alteration of the phase transition parameters (T(p), T(m), AT 1/4 ΔH(p), ΔI-I(m)) measured by DSC. It was observed that some phase transition parameters were affected by all polymers but in different extent. PVA-Prol copolymer exibited a prominent effect in increasing the membrane coop- erativity. The influence of PVA-Bul was unique; it decreased the cooperativity of phospholipid molecules. It was also shown that the lipid membranepolymer interac- tion considerably depends on both the chemical structure and the molecular mass of the polymers.
|Translated title of the contribution||Study of the interaction of lipidmembrane and neutral polymers by DSC|
|Number of pages||6|
|Journal||Acta pharmaceutica Hungarica|
|Publication status||Published - Nov 1 1997|
ASJC Scopus subject areas
- Pharmaceutical Science