Aher Naval Dinesh, Nair Hema Ajit
Department of Pharmaceutics, Bombay College of Pharmacy, Kalina, Santacruz East, Mumbai 400 098, India.
ScientificWorldJournal. 2014 Jan 2;2014:297603. doi: 10.1155/2014/297603. eCollection 2014.
Thiomers could prove to be suitable mucoadhesives for fabrication of ocular inserts.
The study intends to explore the application of thiolated sodium alginate (TSA) to the preparation of bilayered ocular inserts of gatifloxacin.
Cysteine moieties were grafted onto sodium alginate (SA) and the resultant thiomer was characterized for relevant physicochemical properties. Bilayered inserts were fabricated with a mucoadhesive immediate release layer composed of either SA or TSA and a sustained release layer composed of acrylates. Films were prepared by solvent evaporation and evaluated for mechanical properties, drug content, and in vitro release.
The synthesized TSA possessed 248.80 ± 49.7 μ mol thiol groups/gm and its solutions thickened on standing due to disulphide bridging. Its films showed improved mucoadhesion and also a strikingly beneficial property of resisting erosion and remaining as a hydrated adhesive layer for the duration of drug release. The bilayered films were found to be flexible, with good folding endurance, uniform thickness, and appropriate drug content, and showed a release of about 80% of loaded gatifloxacin in 12 h.
The study demonstrates promise in employing thiolated polymer in conjunction with acrylates for the design of ocular inserts for twice a day therapy with gatifloxacin.
硫醇聚合物可能被证明是制备眼用插入剂的合适黏膜黏附剂。
本研究旨在探索巯基化海藻酸钠（TSA）在制备加替沙星双层眼用插入剂中的应用。
将半胱氨酸部分接枝到海藻酸钠（SA）上，并对所得硫醇聚合物的相关物理化学性质进行表征。双层插入剂由SA或TSA组成的黏膜黏附速释层和丙烯酸酯组成的缓释层制成。通过溶剂蒸发制备薄膜，并对其机械性能、药物含量和体外释放进行评估。
合成的TSA具有248.80±49.7μmol巯基/克，其溶液由于二硫键桥连而在静置时变稠。其薄膜表现出改善的黏膜黏附性，并且还具有显著有益的特性，即抗侵蚀并在药物释放期间作为水合黏附层保留。发现双层薄膜具有柔韧性、良好的耐折叠性、均匀的厚度和合适的药物含量，并且在12小时内释放约80%的负载加替沙星。
本研究表明，将巯基化聚合物与丙烯酸酯结合用于设计每日两次使用加替沙星的眼用插入剂具有前景。
