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Effects of poly (ethylene glycol) chains conformational transition on the properties of mixed DMPC/DMPE-PEG thin liquid films and monolayers.
| Content Provider | Semantic Scholar |
|---|---|
| Author | Georgiev, Georgi As Sarker, Dipak K. Al-Hanbali, Othman Georgiev, Georgi D. Lalchev, Zdravko |
| Copyright Year | 2007 |
| Abstract | Foam thin liquid films (TLF) and monolayers at the air-water interface formed by DMPC mixed with DMPE-bonded poly (ethylene glycol)s (DMPE-PEG(550), DMPE-PEG(2000) and DMPE-PEG(5000)) were obtained. The influence of both (i) PEG chain size (evaluated in terms of Mw) and mushroom-to-brush conformational transition and (ii) of the liposome/micelle ratio in the film-forming dispersions, on the interfacial properties of mixed DMPC/DMPE-PEG films was compared. Foam film studies demonstrated that DMPE-PEG addition to foam TLFs caused (i) delayed kinetics of film thinning and black spot expansion and (ii) film stabilization. At the mushroom-to-brush transition, due to steric repulsion increased DMPE-PEG films thickness reached 25 nm while pure DMPC films were only 8 nm thick Newton black films. It was possible to differentiate DMPE-PEG(2000/5000) from DMPE-PEG(550) by the ability to change foam TLF formation mechanism, which could be of great importance for "stealth" liposome design. Monolayer studies showed improved formation kinetics and equilibrium surface tension decrease for DMPE-PEG monolayers compared with DMPC pure films. SEM observations revealed "smoothing" and "sealing" of the defects in the solid-supported layer surface by DMPE-PEGs adsorption, which could explain DMPE-PEGs ability to stabilize TLFs and to decrease monolayer surface tension. All effects in monolayers, foam TLFs and solid-supported layers increased with the increase of PEG Mw and DMPE-PEG concentration. However, at the critical DMPE-PEG concentration (where mushroom-to-brush conformational transition occurred) maximal magnitude of the effects was reached, which only slightly changed at further DMPE-PEG content and micelle/liposome ratio increase. |
| Starting Page | 27 |
| Ending Page | 27 |
| Page Count | 1 |
| File Format | PDF HTM / HTML |
| Alternate Webpage(s) | http://www.philadelphia.edu.jo/research_papers/Colloid_and_Surfaces.pdf |
| PubMed reference number | 17587556v1 |
| Volume Number | 59 |
| Issue Number | 2 |
| Journal | Colloids and surfaces. B, Biointerfaces |
| Language | English |
| Access Restriction | Open |
| Subject Keyword | 1,2-dimyristoylphosphatidylethanolamine Dimyristoylphosphatidylcholine Equilibrium Ethylene Dibromide Kinetics Liposomes Poly A Poly I-C Polyethylene Glycols Smoothing (statistical technique) Surface Tension anatomical layer ethylene glycol peginterferon alfa-2b technetium Tc 99m bis(1,2-dimethylphosphino)ethane |
| Content Type | Text |
| Resource Type | Article |
