State Key Laboratory of Fine Chemicals, Department of Polymer Science and Engineering, School of Chemical Engineering, Dalian University of Technology, Dalian 116024, China.
J Mater Chem B. 2019 Apr 14;7(14):2261-2276. doi: 10.1039/c8tb02952k. Epub 2019 Mar 11.
In this work, we developed a facile end-functionalization method using hydroxylated coumarin to initiate the ring-opening polymerization of cyclic esters to synthesize a series of fluorescent biodegradable aliphatic polyesters with tailorable properties. The resulting fluorescent functionalized poly(l-lactide) (PLLA-COU), poly(ε-caprolactone) (PCL-COU) poly(δ-valerolactone) (PVL-COU) and poly(trimethylene carbonate) (PTMC-COU) were investigated to evaluate the dependence of fluorescence on the chemical structure and molecular weight of the materials. The differences in the electron withdrawing ability and the density of ester groups are responsible for the changes in the fluorescence quantum yield. Then, two representative biodegradable materials, namely, PLLA-COU and PCL-COU, were used to prepare fluorescent paclitaxel-loaded microspheres. During in vitro drug release, the release rate of the PCL-COU microspheres is dramatically faster than that of the PLLA-COU microspheres due to the difference in the material nature and their surface morphologies, possibly achieving a tunable degradation and release rate for the drug carriers. Fluorescent functionalized polyester microspheres can retain their fluorescence properties and emit bright blue light for fluorescence tracing during the degradation process. Biological evaluations showed that both fluorescent polyesters are devoid of any significant toxicity and have good biocompatibility. The results demonstrated that the obtained fluorescent polyesters are promising for use in traceable and controlled drug delivery with tunable drug release.
在这项工作中，我们开发了一种简便的端基官能化方法，使用羟基化香豆素来引发环状酯的开环聚合，以合成一系列具有可调节性能的荧光可生物降解脂肪族聚酯。所得荧光功能化聚（L-丙交酯）（PLLA-COU）、聚（ε-己内酯）（PCL-COU）、聚（δ-戊内酯）（PVL-COU）和聚（三亚甲基碳酸酯）（PTMC-COU）被用于评估荧光对材料化学结构和分子量的依赖性。电子吸电子能力和酯基密度的差异导致荧光量子产率的变化。然后，使用两种代表性的可生物降解材料，即 PLLA-COU 和 PCL-COU，来制备荧光紫杉醇负载微球。在体外药物释放过程中，由于材料性质和表面形貌的差异，PCL-COU 微球的释放速率明显快于 PLLA-COU 微球，可能实现药物载体的可调节降解和释放速率。荧光功能化聚酯微球在降解过程中可以保留其荧光性能，并发出明亮的蓝光进行荧光跟踪。生物评价表明，两种荧光聚酯均无明显毒性，具有良好的生物相容性。结果表明，所得到的荧光聚酯在具有可调节药物释放的示踪和控制药物递送方面具有广阔的应用前景。
