Gupta Himanshu, Aqil M, Khar R K, Ali Asgar, Bhatnagar Aseem, Mittal Gaurav
Department of Pharmacy and Pharmaceutical Sciences, University of Toledo, Toledo, OH 43614, USA.
Department of Pharmaceutics, Faculty of Pharmacy, Jamia Hamdard, New Delhi, India.
J Pharm Bioallied Sci. 2015 Jan-Mar;7(1):9-14. doi: 10.4103/0975-7406.149810.
Delivering drugs to ocular region is a challenging task. Eye physiological barriers lead to relatively less therapeutic and bioavailability effect by the conventional eye drops. This may be overcome by the use of in situ gel delivery system.
The objective of our work was to formulate an ocular delivery system of levofloxacin, based on the concept of ion (sodium alginate) and pH (chitosan) activated in situ gelation concept. Due to its elastic properties, in situ gels resist the ocular drainage of drug leading to longer contact times with ocular surface.
The formulation was evaluated for physicochemical characteristics, in vitro drug release. Ocular retention studies were carried out by Gamma scintigraphy. Time activity curve was plotted between marketed formulation and developed formulation for comparing drug drainage from the eye with time. Ocular tolerance test was performed by handheld infra-red camera.
The formulations showed a first-order release pattern over 12 h. Both in vitro release studies and in vivo gamma scintigraphy precorneal retention studies indicated better therapeutic efficacy compared with standard eye drops.
The results demonstrated that the developed in situ gel of levofloxacin is nonirritant, has prolonged action and is a better option in terms of retention, ocular bioavailability and patient compliance when compared with plain eye drops formulation.
将药物递送至眼部是一项具有挑战性的任务。眼部生理屏障导致传统眼药水的治疗效果和生物利用度相对较低。使用原位凝胶递送系统可能会克服这一问题。
我们工作的目的是基于离子(海藻酸钠)和pH(壳聚糖)激活的原位凝胶化概念,制备左氧氟沙星眼部递送系统。由于其弹性特性,原位凝胶可抵抗药物的眼部引流,从而延长与眼表的接触时间。
对该制剂进行了理化特性、体外药物释放评估。通过γ闪烁显像进行眼部滞留研究。绘制市售制剂和研发制剂之间的时间-活性曲线,以比较药物随时间从眼部的引流情况。通过手持式红外相机进行眼部耐受性测试。
该制剂在12小时内呈现一级释放模式。体外释放研究和体内γ闪烁显像角膜前滞留研究均表明,与标准眼药水相比,其治疗效果更佳。
结果表明,所研发的左氧氟沙星原位凝胶无刺激性,作用时间延长,与普通眼药水制剂相比,在滞留、眼部生物利用度和患者依从性方面是更好的选择。