Liu Zhidong, Li Jiawei, Nie Shufang, Liu Hui, Ding Pingtian, Pan Weisan
Department of Pharmacy, Shenyang Pharmaceutical University, Shenyang 110016, China.
Int J Pharm. 2006 Jun 6;315(1-2):12-7. doi: 10.1016/j.ijpharm.2006.01.029. Epub 2006 Apr 17.
The poor bioavailability and therapeutic response exhibited by conventional ophthalmic solutions due to rapid pre-corneal elimination of the drug may be overcome by the use of in situ gel-forming systems that are instilled as drops into the eye and then undergo a sol-gel transition in the cul-de-sac. The present work describes the formulation and evaluation of an ophthalmic delivery system of an antibacterial agent, gatifloxacin, based on the concept of ion-activated in situ gelation. Alginate (Kelton) was used as the gelling agent in combination with HPMC (Methocel E50Lv) which acted as a viscosity-enhancing agent. The rheological behaviors of all formulations were not affected by the incorporation of gatifloxacin. Both in vitro release studies and in vivo pre-corneal retention studies indicated that the alginate/HPMC solution retained the drug better than the alginate or HPMC E50Lv solutions alone. These results demonstrate that the alginate/HPMC mixture can be used as an in situ gelling vehicle to enhance ocular bioavailability and patient compliance.
由于药物在角膜前的快速消除，传统眼科溶液表现出较差的生物利用度和治疗反应，而通过使用原位凝胶形成系统可以克服这一问题，该系统以滴剂形式滴入眼内，然后在眼穹窿处发生溶胶-凝胶转变。本研究基于离子激活原位凝胶化的概念，描述了抗菌剂加替沙星的眼科给药系统的配方和评价。海藻酸钠（Kelton）与作为增稠剂的羟丙基甲基纤维素（Methocel E50Lv）联合用作胶凝剂。所有制剂的流变行为均不受加替沙星加入的影响。体外释放研究和体内角膜前滞留研究均表明，海藻酸钠/羟丙基甲基纤维素溶液比单独的海藻酸钠或羟丙基甲基纤维素E50Lv溶液能更好地保留药物。这些结果表明，海藻酸钠/羟丙基甲基纤维素混合物可作为原位凝胶载体，以提高眼部生物利用度和患者顺应性。
