The microemulsion systems of polyoxyethylene-10-oleyl ether/oil/water have been studied. The medium chain triglycerides (MCT) and retinyl palmitate mixture (1:1, w/w) was solubilized up to 9% w/w at the surfactant concentration of 25% w/w. The lowest phase inversion temperature (PIT) of the microemulsion solutions was about 57°C and showed no phase separation for 6 months at room temperature. The critical micelle concentration (CMC) of polyoxyethylene-10-oleyl ether (C18:1E10) was 1.20×10-5 M at 27°C. The phase behavior and pulsed field gradient NMR data clearly indicate that these microemulsions are discrete oil-in-water (O/W) microemulsions. The self-diffusion coefficient of free retinyl palmitate, MCT and MCT/retinyl palmitate mixture (1:1, w/w) were 1.61×10-10, 2.60×10-10 and 2.59×10 -10 m2 s-1, respectively. The D of free C 18:1E10 was 4.96×10-11 m2 s-1. The relative self-diffusion coefficients of water and oil differed by more than 1 order of magnitude. The hydrodynamic radius (R H) of this oil swollen micelle was calculated as 14 nm at 1% w/w oil concentration (23% w/w C18:1E10, 0.5% w/w MCT, 0.5% w/w retinyl palmitate, 76% w/w water) and increased to 34 nm at 7% w/w oil concentration (23% w/w C18:1E10, 3.5% w/w MCT, 3.5% w/w retinyl palmitate, 70% w/w water).
|Number of pages||9|
|Journal||Colloids and Surfaces A: Physicochemical and Engineering Aspects|
|Publication status||Published - 2003 Apr 15|
Bibliographical noteFunding Information:
This work was sponsored by the VIXXOL Corporation (Kyonggi-do, Korea). We are grateful to Mr. K.H. Kim for his support.
- Critical micelle concentration
- Polyoxyethylene-10-oleyl ether
- Retinyl palmitate
- Self-diffusion coefficients
ASJC Scopus subject areas
- Surfaces and Interfaces
- Physical and Theoretical Chemistry
- Colloid and Surface Chemistry