Novel A-B-A triblock copolymers based on poly(l-lactic acid) (PLLA) were designed with an ad hoc chemical structure to prepare micro- and nanoparticles for controlled drug delivery. A block is formed by PLLA, while central B block is a copolymeric system based on poly(butylene succinate) and poly(triethylene succinate): more specifically, two copolymers with fix composition (50:50 mol:mol) and different molecular architecture were synthesized. One of them is characterized by a block architecture, i.e. long butylene succinate and triethylene succinate sequences form the macromolecular chains, the other being on the contrary a random copolymer with short sequences. The so-obtained materials were characterized from the molecular and thermal point of view. Moreover, to investigate the effect of both chemical structure and molecular architecture of the polymers synthesized on drug release kinetics, Dexamethasone-encapsulated micro- and nanoparticles were prepared by oil-in-water miniemulsion technique. These particles were subjected to thermal and morphological characterization. After that, drug release studies were carried out, and the effect of chemical composition, sequence distribution and particle size on release profile was evaluated.

临时设计了基于聚（1-乳酸）（PLLA）的新型ABA三嵌段共聚物化学结构以制备可控药物递送的微米和纳米颗粒。嵌段是由PLLA形成的，而中心B嵌段是基于聚丁二酸丁二酯和聚丁二酸三乙烯酯的共聚体系：更具体地说，两种具有固定组成（50:50 mol：mol）和不同分子结构的共聚物是合成的。它们之一的特征在于嵌段结构，即长丁二酸丁二酯和丁二酸三乙二酯序列形成大分子链，相反，另一种是具有短序列的无规共聚物。从分子和热学角度对如此获得的材料进行了表征。此外，要研究合成的聚合物的化学结构和分子结构对药物释放动力学的影响，通过水包油微乳液技术制备了地塞米松包裹的微粒和纳米颗粒。对这些颗粒进行热和形态表征。此后，进行了药物释放研究，并评估了化学组成，序列分布和粒径对释放曲线的影响。