The eye consists of sensitive, compactly adjoined tissue structures which act as strong physical (static) and physiological (dynamic) barriers that prevent entry of foreign bodies into the eye. Together, these barriers reduce the bioavailability of topically and intraocularly administered medicaments thus demanding frequent drug administration for the treatment of chronic eye diseases. Hence, development of drug delivery systems (DDS) that can be retained in ocular tissues for longer durations can help to reduce the frequency of drug administration, whereas, delivery systems that traverse through ocular barriers may offer higher bioavailability of administered drugs to otherwise inaccessible ocular tissues. These objectives can be partially/fully achieved using nanoparticulate/colloidal DDS. Colloidal DDS, due to their nanodimensions, undergo internalization by cells which enables transport of drugs through ocular barriers. Furthermore, nanoparticles can prolong duration of drug release and can increase residence time of entrapped cargo molecules in ocular tissues. Together, these aspects facilitate a higher bioavailability, prolonged therapeutic effect and reduced frequency of drug administration for the effective treatment of chronic ocular diseases. Hence, nanocarriers have been widely explored for ophthalmic drug delivery applications. In this review, we discuss the anatomy of ocular tissues along with their barrier properties. We then discuss ocular diseases along with the various routes of drug administration and pathways of drug transport in the eye. The next section discusses the influence of physicochemical properties of therapeutic molecules on their ocular distribution and conventional and advanced (nanoparticulate/colloidal DDS) drug formulations that are used for the treatment of ocular diseases. This article is categorized under: Therapeutic Approaches and Drug Discovery > Nanomedicine for Neurological Disease Therapeutic Approaches and Drug Discovery > Emerging Technologies Nanotechnology Approaches to Biology > Nanoscale Systems in Biology.

中文翻译：

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眼部疾病的基础知识，挑战和基于纳米医学的解决方案。

眼睛由敏感，紧密相连的组织结构组成，这些组织结构充当防止异物进入眼睛的强力物理（静态）和生理（动态）屏障。这些障碍一起降低了局部和眼内给药药物的生物利用度，因此需要频繁给药以治疗慢性眼病。因此，开发可以在眼组织中保留更长时间的药物输送系统（DDS）可以帮助减少药物给药的频率，而穿越眼屏障的输送系统可以为其他无法进入的眼提供更高的生物利用度组织。使用纳米颗粒/胶体DDS可以部分/完全实现这些目标。胶体DDS，由于其纳米尺寸，经历细胞的内在化，使药物能够通过眼屏障转运。此外，纳米颗粒可以延长药物释放的持续时间，并且可以增加被包裹的货物分子在眼组织中的停留时间。总之，这些方面促进了更高的生物利用度，延长的治疗效果以及减少了药物的有效治疗慢性眼病的频率。因此，已经广泛探索了用于眼科药物递送应用的纳米载体。在这篇综述中，我们讨论了眼组织的解剖及其屏障特性。然后，我们讨论眼部疾病以及药物在眼中的各种给药途径和药物运输途径。下一节讨论了治疗分子的理化特性对其眼部分布以及用于治疗眼部疾病的常规和高级（纳米颗粒/胶体DDS）药物制剂的影响。本文归类于：治疗方法和药物发现>用于神经疾病的纳米药物治疗方法和药物发现>生物学的新兴技术纳米技术方法>生物学中的纳米系统。