Abdelbary Ghada, El-Gendy Nashwa
Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmacy, Cairo University, Kaser el aini street, Cairo, Egypt.
AAPS PharmSciTech. 2008;9(3):740-7. doi: 10.1208/s12249-008-9105-1. Epub 2008 Jun 18.
The objective of the present research was to investigate the feasibility of using non-ionic surfactant vesicles (niosomes) as carriers for the ophthalmic controlled delivery of a water soluble local antibiotic; gentamicin sulphate. Niosomal formulations were prepared using various surfactants (Tween 60, Tween 80 or Brij 35), in the presence of cholesterol and a negative charge inducer dicetyl phosphate (DCP) in different molar ratios and by employing a thin film hydration technique. The ability of these vesicles to entrap the studied drug was evaluated by determining the entrapment efficiency %EE after centrifugation and separation of the formed vesicles. Photomicroscopy and transmission electron microscopy as well as particle size analysis were used to study the formation, morphology and size of the drug loaded niosomes. Results showed a substantial change in the release rate and an alteration in the %EE of gentamicin sulphate from niosomal formulations upon varying type of surfactant, cholesterol content and presence or absence of DCP. In-vitro drug release results confirmed that niosomal formulations have exhibited a high retention of gentamicin sulphate inside the vesicles such that their in vitro release was slower compared to the drug solution. A preparation with 1:1:0.1 molar ratio of Tween 60, cholesterol and DCP gave the most advantageous entrapment (92.02% +/- 1.43) and release results (Q(8h) = 66.29% +/- 1.33) as compared to other compositions. Ocular irritancy test performed on albino rabbits, showed no sign of irritation for all tested niosomal formulations.
本研究的目的是探讨使用非离子表面活性剂囊泡(脂质体)作为载体用于眼科控释水溶性局部抗生素硫酸庆大霉素的可行性。脂质体制剂是在胆固醇和负电荷诱导剂磷酸二鲸蜡酯(DCP)存在的情况下,使用各种表面活性剂(吐温60、吐温80或Brij 35),以不同摩尔比,采用薄膜水化技术制备的。通过离心和分离形成的囊泡后测定包封率%EE来评估这些囊泡包封所研究药物的能力。利用光学显微镜、透射电子显微镜以及粒径分析来研究载药脂质体的形成、形态和大小。结果表明,随着表面活性剂类型、胆固醇含量以及DCP的存在与否的变化,硫酸庆大霉素从脂质体制剂中的释放速率发生了显著变化,包封率也有所改变。体外药物释放结果证实,脂质体制剂在囊泡内对硫酸庆大霉素具有较高的保留率,因此其体外释放比药物溶液慢。与其他组合物相比,吐温60、胆固醇和DCP摩尔比为1:1:0.1的制剂具有最有利的包封率(92.02%±1.43)和释放结果(Q(8h)=66.29%±1.33)。对白化兔进行的眼刺激性试验表明,所有测试的脂质体制剂均无刺激迹象。