中文名称：聚乙丙交酯-b-聚乙二醇-b-聚乙丙交酯(x/y/x)

英文名称：PLGA-b-PEG-b-PLGA

PLGA-PEG-PLGA是由亲水性嵌段聚乙二醇（PEG)和疏水性嵌段聚丙交酯-乙交酯（PLGA）组成的两亲性BAB三嵌段共聚物。由于其优异的性能，可用于制作生物可降解温敏水凝胶；具有可生物降解和生物相容性聚酯链段的聚乙二醇化共聚物还可用于制备核-壳胶束，纳米颗粒和微球。产品末端的活性基团可以链接一些修饰多肽、蛋白、糖类、叶酸或抗体等等，使其具有主动靶向作用。 聚酯链段的水解降解能力取决于分子量和酯基（丙交酯，乙交酯或己内酯）之间的间隔基。 PEG-PLGA可以溶解在一系列常见的有机溶剂中，具体取决于其组成，尤其是LA对GA的比例和PLGA的总分子量。随着分子量的增加和GA含量的增加，其在普通有机溶剂中的溶解度变差。通常，较低的分子量或更高的LA含量的PEG-PLGA可以更容易地溶于氯化溶剂（如二氯甲烷或氯仿）中，有时根据总分子量溶于水可混溶的溶剂（如丙酮，乙腈和THF）中。 GA含量较高的PEG-PLGA可以更好地被六氟异丙醇之类的氟化溶剂溶解。

PLGA-PEG-PLGA is an amphiphilic bab triblock copolymer composed of hydrophilic block polyethylene glycol (PEG) and hydrophobic block polylactide glycolide (PLGA). Because of its excellent properties, it can be used to prepare biodegradable thermosensitive hydrogels. Pegylated copolymers with biodegradable and biocompatible polyester segments can also be used to prepare core-shell micelles, nanoparticles and microspheres. The active group at the end of the product can link some modified peptides, proteins, sugars, folic acid or antibodies to make it have active targeting effect. The hydrolytic degradation ability of polyester segments depends on the molecular weight and the spacer between ester groups (lactide, glycolide or caprolactone). Peg-plga can be dissolved in a series of common organic solvents, depending on its composition, especially the ratio of La to GA and the total molecular weight of PLGA. With the increase of molecular weight and GA content, its solubility in ordinary organic solvents becomes worse. Generally, peg-plga with lower molecular weight or higher La content can be more easily dissolved in chlorinated solvents (such as dichloromethane or chloroform), and sometimes in water miscible solvents (such as acetone, acetonitrile and THF) according to the total molecular weight. Peg-plga with higher GA content can be better dissolved by fluorinated solvents such as hexafluoroisopropanol.