Amanatfard Arezoo, Khazaeli Payam, Pardakhty Abbas, Najafi Moslem Lari, Mohammadi Amin
Pharmaceutics Research Center, Insitute of Neuropharmacology, Kerman University of Medical Sciences, Kerman, Iran.
Int J Pharm Investig. 2015 Oct-Dec;5(4):259-65. doi: 10.4103/2230-973X.167691.
The insect repellent compounds are used to protect humans, animals and plants against insect bites. Aromatic amides have insect repellent effects. N,N-diethyl-meta-toluamide (DEET) (C12 H17 NO) is one of the best insect repellents has been used for many years. DEET is a colorless, odorless liquid that is approximately insoluble in water and soluble in glycerin, ethanol, and isopropyl alcohol. Due to the solubility problem of DEET, its topical formulations usually have alcoholic bases, but these kind of formulations increase skin permeation and also systemic absorption of DEET, which leads to some toxic effects. The main goal of this study was to prepare the formulation of DEET niosomes in a topical dosage form with suitable stability properties.
Three different methods were used to prepare niosome formulations: Dehydration rehydration vesicle method, direct mixing method, homogenizer method. Sorbitan surfactants, cholesterol, polyoxyethylenecetyl, phosphate buffer (pH 7.4), and charge inductive compounds like cetyltrimethylammonium bromide were used to provide a net negative charge to the final membrane structure. A high-performance liquid chromatography method was then used for the determination of the loaded DEET.
A large number of niosomes were multi-layered and have a spherical shape. In comparison, syringe method against direct mixing is more appropriate because of creation MLV and uniform niosomes but the best method is homogenizer method. Drug entrapment was between 14% and 21% in selected formulation.
According to this study, homogenizing method can be used for formulation of DEET in niosome form in topical formulations.
驱虫化合物用于保护人类、动物和植物免受昆虫叮咬。芳香酰胺具有驱虫作用。N,N-二乙基间甲苯酰胺（避蚊胺，DEET）（C12H17NO）是多年来使用的最佳驱虫剂之一。避蚊胺是一种无色、无味的液体，几乎不溶于水，可溶于甘油、乙醇和异丙醇。由于避蚊胺的溶解性问题，其局部用制剂通常含有酒精基质，但这类制剂会增加避蚊胺的皮肤渗透和全身吸收，从而导致一些毒性作用。本研究的主要目的是以具有合适稳定性的局部剂型制备避蚊胺脂质体。
采用三种不同方法制备脂质体制剂：脱水再水化囊泡法、直接混合法、匀化器法。使用脱水山梨醇表面活性剂、胆固醇、聚氧乙烯十六烷基醚、磷酸盐缓冲液（pH 7.4）以及十六烷基三甲基溴化铵等电荷诱导化合物，使最终的膜结构带净负电荷。然后采用高效液相色谱法测定负载的避蚊胺。
大量脂质体为多层结构且呈球形。相比之下，注射器法比直接混合法更合适，因为它能形成多层囊泡和均匀的脂质体，但最佳方法是匀化器法。在选定的制剂中，药物包封率在14%至21%之间。
根据本研究，匀化法可用于局部制剂中以脂质体形式制备避蚊胺。
