Iscan Y, Hekimoglu S, Sargon M F, Hincal A A
Department of Pharmaceutical Technology, Faculty of Pharmacy, Hacettepe University, Ankara, Turkey.
J Microencapsul. 2006 May;23(3):315-27. doi: 10.1080/02652040500444198.
DEET (N,N-diethyl m-toluamide) is a lipophilic compound which has a common use as an insect repellent and causes not only skin irritation but also systemic side effects at high concentrations in long-term skin application. In this study, DEET is incorporated into solid lipid particles, a colloidal drug delivery system, in order to reduce the percutaneous permeation and avoid toxic effects and also maintain drug effectiveness on the skin surface for a long duration of insect repellence. Solid lipid particles were prepared based on emulsion systems at different concentrations and after the characterization studies, the formulation with 20% lipid phase and 1:1 drug:lipid ratio was carried to in vitro release and skin permeation studies. Solid lipid particles with DEET were compared to free DEET using cream and hydrophilic gel vehicles. Results showed that incorporation of DEET into solid lipid particles reduced the release rate and skin permeation of DEET. Imaging studies using scanning electron microscopy showed that there were still solid lipid particles on skin surface after 2 h indicating that DEET could be present for a longer time on the application site.
避蚊胺（N,N-二乙基间甲苯酰胺）是一种亲脂性化合物，常用作驱虫剂，长期皮肤涂抹高浓度的避蚊胺不仅会引起皮肤刺激，还会产生全身副作用。在本研究中，将避蚊胺载入固体脂质颗粒（一种胶体药物递送系统）中，以减少其经皮渗透，避免毒性作用，并在皮肤表面长时间保持驱避昆虫的药效。基于不同浓度的乳液体系制备了固体脂质颗粒，经过表征研究后，对脂质相浓度为20%、药物与脂质比例为1:1的制剂进行了体外释放和皮肤渗透研究。将含有避蚊胺的固体脂质颗粒与使用乳膏和亲水凝胶载体的游离避蚊胺进行比较。结果表明，将避蚊胺载入固体脂质颗粒中可降低避蚊胺的释放速率和皮肤渗透率。使用扫描电子显微镜进行的成像研究表明，2小时后皮肤表面仍有固体脂质颗粒，这表明避蚊胺在涂抹部位的存在时间可能更长。
