In this paper, a three-dimensional (3D) poly(lactic-co-glycolic acid) (PLGA)/silica colloidal crystal drug delivery system with sustained drug release and visualized release monitoring was developed. This system had employed silica colloidal crystal microparticles as template skeleton, PLGA as drug carrier and dexamethasone (DEX) as therapeutic agent. The fabrication of the microparticle-based system included droplet formation based-on microfluidics, silica nanoparticle self-assembly and layer-by-layer deposition of PLGA containing DEX. In 370 μm droplets, the silica colloidal nanoparticles could self-assemble orderly into microparticles with a diameter of 187 μm, featuring red structure color. During the deposition of PLGA with the drug into the voids of the template microparticles, the reflection peak red-shifted and weakened until the voids were completely filled. Owing to the gradual degradation of PLGA, the release of DEX was triggered and sustained for 4 weeks with a cumulative release of 94.9%, while the structure color of the microparticles recovered during the release process. The color change could be recognized by the naked eyes, which would benefit the non-invasive monitoring of the drug release. The in vitro cytotoxicity and long-term inhibiting proliferation were investigated on retinal pigment epithelial cells. The inhibition effect of DEX released from the microparticles showed concentration-dependence from 40 to 200 μg mL⁻¹ and time-dependence within 7 days. As a sustained drug delivery system with self-reporting drug release, the particles have potential applications in treatment of intraocular diseases.

在本文中，一个三维（3D）的聚（乳酸-共开发了具有持续药物释放和可视化释放监测功能的β-乙醇酸（PLGA）/二氧化硅胶体晶体药物输送系统。该系统以二氧化硅胶体晶体微粒为模板骨架，PLGA为药物载体，地塞米松（DEX）为治疗剂。基于微粒的系统的制造包括基于微流体的液滴形成，二氧化硅纳米粒子自组装和含DEX的PLGA的逐层沉积。在370μm的液滴中，二氧化硅胶体纳米颗粒可以有序地自组装成直径为187μm的具有红色结构颜色的微粒。在PLGA与药物一起沉积到模板微粒的空隙中期间，反射峰红移并减弱，直到空隙被完全填充。由于PLGA的逐渐降解，DEX的释放被触发并持续4周，累积释放为94.9％，而微粒的结构颜色在释放过程中得以恢复。肉眼可以识别颜色的变化，这将有利于对药物释放进行无创监测。研究了视网膜色素上皮细胞的体外细胞毒性和长期抑制增殖。从微粒中释放出的DEX的抑制作用表现出40至200μgmL的浓度依赖性 这将有利于对药物释放进行无创监测。研究了视网膜色素上皮细胞的体外细胞毒性和长期抑制增殖。从微粒中释放出的DEX的抑制作用表现出40至200μgmL的浓度依赖性 这将有利于对药物释放进行无创监测。研究了视网膜色素上皮细胞的体外细胞毒性和长期抑制增殖。从微粒中释放出的DEX的抑制作用表现出40至200μgmL的浓度依赖性^-1和7天之内的时间依赖性。作为具有自我报告药物释放的持续药物传递系统，这些颗粒在眼内疾病的治疗中具有潜在的应用。