PDF(Pubmed)
Abstract：
Posterior segment disease acts as a major cause of irreversible visual impairments. Successful treatment of posterior segment disease requires the efficient delivery of therapeutic substances to the targeted lesion. However, the complex ocular architecture makes the bioavailability of topically applied drugs extremely low. Invasive delivery approaches like intravitreal injection may cause adverse complications. To enhance the efficiency, several biomedical engineering systems have been developed to increase the penetration efficiency and improve the bioavailability of drugs at the posterior segments. Advantageously, biodegradable microspheres are found to deliver the therapeutic agents in a controlled fashion. The microspheres prepared from novel biomaterials can realize the prolonged release at the posterior segment with minimum side effects. Moreover, it will be degraded automatically into products that are non-toxic to the human body without the necessity of secondary operation to remove the residual polymer matrix. Additionally, biodegradable microspheres have decent thermoplasticity, adjustable hydrophilicity, controlled crystallinity, and high tensile strength, which make them suitable for intraocular delivery. In this review, we introduce the latest advancements in microsphere production technology and elaborate on the biomaterials that are used to prepare microspheres. We discuss systematically the pharmacological characteristics of biodegradable microspheres and compare their potential advantages and limitations in the treatment of posterior segment diseases. These findings would enrich our knowledge of biodegradable microspheres and cast light into the discovery of effective biomaterials for ocular drug delivery.
摘要：
后段疾病是不可逆视力障碍的主要原因。后段疾病的成功治疗需要将治疗物质有效地递送到目标病变。然而,复杂的眼部结构使得局部应用药物的生物利用度非常低。侵入性递送方法如玻璃体内注射可引起不良并发症。为了提高效率，已经开发了几种生物医学工程系统来提高药物在后段的渗透效率和生物利用度。有利的是,发现可生物降解的微球以受控的方式递送治疗剂。由新型生物材料制备的微球可以在后段实现延长释放，副作用最小。此外，它将自动降解为对人体无毒的产品，而无需进行二次操作以去除残留的聚合物基质。此外,可生物降解的微球具有良好的热塑性，可调节的亲水性，控制结晶度，和高抗拉强度，这使得它们适合眼内递送。在这次审查中,我们介绍了微球生产技术的最新进展，并详细介绍了用于制备微球的生物材料。我们系统地讨论了生物可降解微球的药理特性，并比较了它们在治疗后段疾病中的潜在优势和局限性。这些发现将丰富我们对生物可降解微球的知识，并有助于发现有效的眼部药物递送生物材料。
