Mishra Vijay, Jain N K
Pharmaceutics Research Laboratory, Department of Pharmaceutical Sciences, Dr. Hari Singh Gour Central University, Sagar, MP 470003, India.
Int J Pharm. 2014 Jan 30;461(1-2):380-90. doi: 10.1016/j.ijpharm.2013.11.043. Epub 2013 Nov 28.
The present investigation was aimed to develop topically effective acetazolamide loaded poly(propylene imine) dendrimer nanoarchitectures and evaluate their intraocular pressure lowering potential. The 5.0G PPI dendrimers were synthesized using ethylendiamine as dendrimer core through divergent approach and characterized and loaded with acetazolamide (ACZ). The developed dendrimeric formulations were characterized for size, loading efficiency. The surface morphology of dendrimer was studied by Transmission Electron Microscopy. The developed dendrimer formulations were evaluated for hemolytic toxicity, ocular irritation index and intra ocular pressure reduction using normotensive adult male New Zealand albino rabbits as in vivo model. The maximum drug entrapment efficiency was found to be 56±2.3%. The in vitro release data of ACZ-5.0G PPI dendrimers showed sustained release of ACZ which was found to be 83.5±1.8 and 80.4±1.6% in phosphate buffer saline (pH 7.4) and simulated tear fluid (pH 7.4), respectively in 24h. Ocular irritancy, ocular residence time and intraocular pressure lowering effect were performed. The study revealed that in lower concentrations the aqueous solutions of dendrimer formulations were found to be weakly irritant to the eyes. The sustained and prolonged reduction in intraocular pressure suggested that drug entrapped in dendrimers can be used for higher retention in ocular cul-de sac. Further, the PPI dendrimer based formulation seems to enhance the ocular drug residence time and exhibits better intraocular pressure lowering effect for glaucoma treatment, more safely, both in vitro and in vivo.
本研究旨在开发局部有效的载乙酰唑胺聚(丙烯亚胺)树枝状大分子纳米结构,并评估其降低眼压的潜力。以乙二胺为树枝状大分子核心,采用发散法合成了5.0G PPI树枝状大分子,并对其进行表征,然后负载乙酰唑胺(ACZ)。对所开发的树枝状大分子制剂进行了粒径、载药效率等表征。通过透射电子显微镜研究了树枝状大分子的表面形态。以血压正常的成年雄性新西兰白化兔为体内模型,对所开发的树枝状大分子制剂进行了溶血毒性、眼刺激指数和眼压降低评估。发现最大药物包封率为56±2.3%。ACZ-5.0G PPI树枝状大分子的体外释放数据显示ACZ呈持续释放,在24小时内,在磷酸盐缓冲盐水(pH 7.4)和模拟泪液(pH 7.4)中的释放率分别为83.5±1.8%和80.4±1.6%。进行了眼刺激性、眼内滞留时间和眼压降低效果研究。研究表明,在较低浓度下,树枝状大分子制剂的水溶液对眼睛有轻微刺激。眼压的持续和长期降低表明,包裹在树枝状大分子中的药物可用于在眼结膜囊中更高的滞留。此外,基于PPI树枝状大分子的制剂似乎能延长眼内药物滞留时间,并在体外和体内更安全地表现出更好的降低青光眼眼压的效果。