• Applied Chemistry for Engineering
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• v.26 no.6
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• pp.659-665
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• 2015

Loading of hydrophobic ${\alpha}$-tocopherol into nanostructured lipid carrier (NLC) was performed for improving its oxidative stability. First, various NLCs with different constituents and mixing ratios were prepared and their characteristics were investigated. While the stable NLCs were made when cetyl palmitate (CP) or glyceryl monosterate (GMS) was used as a solid lipid, the phase separation occurred in the NLCs consisting of stearic acid. Particle sizes of the NLCs were several hundreds of nanometers and the size decreased with increasing the ratio of solvent to lipid. It was examined from DSC thermogram and anisotropy test that the degree of crystallinity of the lipid phase decreased and the lipid matrix became less ordered when octyldodecanol, a long chain fatty alcohol, was added into the solid lipid. The oxidative stability of ${\alpha}$-tocopherol in NLC was remarkably improved compared to that in solution or emulsion under high temperature ($45^{\circ}C$) and UV radiation, which was verified through DPPH test and peroxide value measurement.

• Journal of Pharmaceutical Investigation
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• v.38 no.1
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• pp.39-43
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• 2008

Cyclosporin A (CyA), a potent immunosuppressive drug used in allogeneic transplants and autoimmune disease, is a typical water-insoluble drug. Recently, nanoparticle carriers were investigated to improve the intestinal absorption of drugs. In this study, CyA-loaded nanostructured lipid carriers (NLCs) were prepared from a hot o/w emulsion using the high pressure homogenization method. The NLCs were consisted of cationic lipids, solid lipids, liquid lipids (oils), surfactant and stabilizer. Encapsulation efficiency of CyA in NLCs was approximately 71%. The average particle size and zeta potential of NLCs were below 250 nm and above +40 mV, respectively. The morphology of NLCs was confirmed by transmission electron microscopy (TEM) analysis. Compared to the CyA powder, higher in vitro release of CyA from NLCs was observed after burst release within 30 min. Thus, CyA-loaded NLCs could be applied not only for parenteral route but also for gastrointestinal administration, which needs further investigation.

• Journal of Pharmaceutical Investigation
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• v.40 no.6
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• pp.373-378
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• 2010

In order to develop a topical preparation which has a high occlusive property with skin moisturization, nano-structured lipid carrier (NLC) systems along with solid lipid nanoparticle (SLN) were designed. Various NLC dispersions were successfully formulated with Compritol 888 ATO as a solid lipid, Labrafil M 1944 CS as an oil, and Tween 80 as a surfactant. The increase of oil content (5 to 50%) led to the decrease in the occlusion factor in the order of SLN > NLC-5 > NLC-15 = NLC-30 > NLC-50. Particle size of lipid particulates was in the range of 100 to 160 nm. NLC-based carbogels were prepared by the employment of humectants such as urea, glycerin, and Tinocare GL to carbomer gel. NLC-30 gel formulations containing 4 or 8 % of lipid particles showed improved occlusive effect in vitro, compared to NLC-free gel base. Even though NLC-free gel base revealed comparable occlusion effect by itself, the occlusion factor of 4 % NLC-30 gel was about 2-fold higher than that of NLC-free gel base.