Aims: To evaluate the influence of minor differences in molecular weights of commercially available low molecular weight PLGA grades on the kinetics of doxorubicin release from the nanoparticles.Methods: Three low-molecular weight 50/50 PLGA polymers were thoroughly characterised concerning intrinsic viscosity, molecular weight (Mw), acid value, and residual monomer content. The doxorubicin-loaded nanoparticles prepared using these polymers were evaluated concerning the kinetics of drug release and hydrolytic degradation.Results: The Mw of the polymers were slightly different: 10.2, 10.3, and 4.7 kDa. The nanoparticles obtained from the polymer with Mw of 4.7 kDa exhibited considerably higher rates of drug release and polymer degradation.Conclusion: In the case of low molecular weight PLGA grades even a few kilodaltons could be important for the batch-to-batch reproducibility of the nanoformulation parameters. These results bring forward the importance of in-house characterisation of the polymers to be used for the nanoparticle preparation.

中文翻译：

---

聚合物分子量的细微差异如何影响装载阿霉素的PLGA纳米颗粒降解和药物释放。

目的：评估市售低分子量PLGA品级的分子量的微小差异对纳米粒子释放阿霉素的动力学的影响。方法：彻底表征了三种低分子量50/50 PLGA聚合物的特性粘度，分子重量（Mw），酸值和残留单体含量。使用这些聚合物制备的载有阿霉素的纳米颗粒在药物释放和水解降解动力学方面进行了评估。结果：聚合物的Mw略有不同：10.2、10.3和4.7 kDa。由分子量为4.7 kDa的聚合物获得的纳米颗粒表现出更高的药物释放和聚合物降解速率。在低分子量PLGA级的情况下，甚至几千道尔顿对于纳米配方参数的批次间重现性也很重要。这些结果提出了用于纳米颗粒制备的聚合物的内部表征的重要性。