Abstract

Background:Conventional delivery systems like solution and suspension are commonly used for the treatment of ocular diseases but have low corneal residence time and hence the duration of effect is limited. These drawbacks of conventional systems can be reduced by preparing bioadhesive chitosan (CH) coated noisome.

Methods: Niosomes (NIM) of carteolol (CT) were developed by the thin-film hydration method and optimised by the Box-Behnken statistical design. Further, the optimised CT-NIM was coated with CH to enhance the ocular residence time . The optimised formulation was evaluated for vesicle size, entrapment efficiency, and in-vitro drug release and transcorneal permeation, histopathology, etc.

Results: CT-NIM-opt showed the vesicle size and entrapment efficiency of 235 ± 3.54 nm, and 70.45 ± 0.87%, respectively. DSC spectra exhibited that CT was completely encapsulated into the CH-CT-NIM matrix. Drug release from CH-CT-NIM-opt was more sustained (68.28 ± 4.2%) than CT-NIM (75.69 ± 4.5% in 12 h) and CT solution (99.89 ± 2.8% in 4 h). The CH-CT-NIM-opt represented a strong bio-adhesion (89.76 ± 3.6%) than CT-NIM-opt (15.65 ± 3.4%). The permeation flux exhibited 1.13-fold higher permeation than CT-NIM and 3.23 fold than CT solution. The corneal hydration was found to be within the limit value. The histopathology study exhibited no structural damage to the cornea . HET-CAM results showed zero scores indicating no bleeding or haemorrhage. CH-CT-NIM-opt was found to be isotonic and exhibited good stability when stored at 4 °C for the stated duration of time.

Conclusion: The above findings suggested that NIM can be a potential carrier for the delivery of CT with better ocular residence time.

摘要

背景：溶液和悬浮液等常规给药系统通常用于治疗眼部疾病，但角膜停留时间短，因此效果持续时间有限。传统系统的这些缺点可以通过制备生物粘附壳聚糖 (CH) 涂层的有害物质来减少。

方法：通过薄膜水合方法开发卡替洛尔（CT）的Niosomes（NIM），并通过Box-Behnken统计设计进行优化。此外，优化的 CT-NIM 涂有 CH 以提高眼停留时间。对优化后的制剂进行囊泡大小、包封率、体外药物释放和经角膜渗透、组织病理学等方面的评估。

结果：CT-NIM-opt 显示囊泡大小和包埋效率分别为 235 ± 3.54 nm 和 70.45 ± 0.87%。DSC 光谱显示 CT 完全包裹在 CH-CT-NIM 基质中。CH-CT-NIM-opt 的药物释放比 CT-NIM（12 小时内 75.69 ± 4.5%）和 CT 溶液（4 小时内 99.89 ± 2.8%）更持久（68.28 ± 4.2%）。CH-CT-NIM-opt 比 CT-NIM-opt (15.65 ± 3.4%) 具有更强的生物粘附性 (89.76 ± 3.6%)。渗透通量比 CT-NIM 高 1.13 倍，比 CT 溶液高 3.23 倍。发现角膜水合作用在极限值内。组织病理学研究显示角膜没有结构性损伤。HET-CAM 结果显示零分表明没有出血或出血。

结论：上述研究结果表明，NIM 可以成为提供具有更好眼停留时间的 CT 的潜在载体。