Vega E, Gamisans F, García M L, Chauvet A, Lacoulonche F, Egea M A
Faculty of Pharmacy, Department of Physical Chemistry, Institute of Nanoscience and Nanotechnology, Barcelona University, Avda. Joan XXIII, s/n, 08028 Barcelona, Spain.
J Pharm Sci. 2008 Dec;97(12):5306-17. doi: 10.1002/jps.21383.
Poly(D,L-lactide-co-glycolide) nanospheres incorporating flurbiprofen were prepared by the solvent displacement technique for purposes of assessing (i) drug-polymer physicochemical interactions, (ii) flurbiprofen release from the polymer matrix and (iii) eye permeation of the drug formulated in the colloidal system. The resulting nanospheres were on average 200-300 nm in size and bore a negative charge (xi-potential around -25 mV). They were shown by atomic force microscopy and transmission electron microscopy to be spherical and regular in shape. Thermal methods, infrared spectroscopy and X-ray diffraction showed that the drug was dispersed inside the particles. These tests evidenced an eutectic mixture meaning more widespread dispersion of the drug in the polymer system. Entrapped flurbiprofen was released in vitro from the polymer system by dissolution and diffusion in high drug loaded nanospheres, whereas those with a lesser load showed only diffusion. The ex vivo corneal permeation study showed that flurbiprofen-loaded nanospheres enhanced drug penetration by about twofold over commercial eye drops containing poly(vinyl alcohol) and by about fourfold over flurbiprofen in pH 7.4 phosphate buffer. The corneal hydration level of each cornea was determined to evaluate potential corneal damage.
采用溶剂置换技术制备了包载氟比洛芬的聚(D,L-丙交酯-共-乙交酯)纳米球,以评估:(i)药物与聚合物的物理化学相互作用;(ii)氟比洛芬从聚合物基质中的释放情况;(iii)该胶体系统中所制备药物的眼部渗透情况。所得纳米球平均粒径为200 - 300 nm,带负电荷(ζ电位约为 -25 mV)。原子力显微镜和透射电子显微镜显示其呈球形且形状规则。热分析方法、红外光谱和X射线衍射表明药物分散在颗粒内部。这些测试证明形成了低共熔混合物,意味着药物在聚合物体系中分散得更广泛。在高载药量的纳米球中,包封的氟比洛芬通过溶解和扩散从聚合物体系中体外释放,而载药量较低的纳米球则仅表现出扩散。离体角膜渗透研究表明,载氟比洛芬纳米球使药物渗透率比含聚乙烯醇的市售眼药水提高了约两倍,比pH 7.4磷酸盐缓冲液中的氟比洛芬提高了约四倍。测定了每只角膜的水合水平以评估潜在的角膜损伤。