Department of Pharmaceutical Technology, University of Ege, Izmir, Turkey.
Int J Pharm. 2011 Sep 15;416(1):136-44. doi: 10.1016/j.ijpharm.2011.06.026. Epub 2011 Jun 23.
The aim of this study was to evaluate the potential application of microemulsions as a transdermal drug delivery for naproxen (Np). The pseudo-ternary phase diagrams were developed for microemulsions composed of isopropyl myristate, Span 80, Labrafil M, Labrasol, and Cremophor EL, ethanol and isopropyl alcohol and 0.5N sodium hydroxide. The final concentration of Np in microemulsion systems was 10% (w/w). The microemulsions were characterised by conductivity, droplet size, viscosity and pH. Moreover, in vitro permeability studies were performed using diffusion cells from rat skin. The permeation rates of Np from microemulsions (M1(Np) and M2(Np)) were higher than the commercial (C) gel formulation. The paw oedema test was performed in rats to evaluate the anti-inflammatory activity of Np. The volume increase in paw oedema after 6hr was 0.71±0.46% with M2(Np), whereas M1(Np) and C exhibited 6.48±2.71% and 14.97±3.15% increases in oedema, respectively. Additionally, a significant analgesic effect was detected in the hot plate and tail-flick tests for all test microemulsion and C formulations when compared with the control. Histopathological examination of the treated skin was performed to investigate changes in skin morphology. In conclusion, the microemulsion formulations, especially the M2(Np) formulation, may be used as an effective alternative for the transdermal delivery of Np.
本研究旨在评估微乳液作为萘普生（Np）经皮给药的潜在应用。假三元相图是为由肉豆蔻酸异丙酯、Span 80、Labrafil M、Labrasol 和 Cremophor EL、乙醇和异丙醇以及 0.5N 氢氧化钠组成的微乳液开发的。微乳液系统中 Np 的最终浓度为 10%（w/w）。微乳液的特性包括电导率、液滴大小、粘度和 pH 值。此外，还使用大鼠皮肤扩散池进行了体外渗透研究。Np 从微乳液（M1（Np）和 M2（Np））中的渗透速率高于商业（C）凝胶制剂。在大鼠中进行爪肿胀试验以评估 Np 的抗炎活性。6 小时后，M2（Np）引起的爪肿胀体积增加为 0.71±0.46%，而 M1（Np）和 C 分别表现出 6.48±2.71%和 14.97±3.15%的肿胀增加。此外，与对照组相比，所有测试的微乳液和 C 制剂在热板和尾巴闪烁测试中均表现出显著的镇痛作用。对处理过的皮肤进行组织病理学检查，以研究皮肤形态的变化。总之，微乳液制剂，特别是 M2（Np）制剂，可作为 Np 经皮给药的有效替代方案。
