For cancer treatment, intratumoral drug injection has many limitations and not commonly adopted. The poly[lactic-co-glycolic acid] (PLGA) has emerged as a promising vehicle to enhance the in vitro/in vivo characteristic of various drugs. We prepared doxorubicin-PLGA microspheres (DOX-PLGA MSs) using the electrospray method. An in vitro elution method was employed to evaluate the release of DOX from the MSs. We performed an in vivo study on rats, in which we directly injected DOX-PLGA MSs into the liver. We measured liver and plasma DOX concentrations to assess local retention and systemic exposure. The mean diameter of the MSs was 6.74 ± 1.01 μm. The in vitro DOX release from the MSs exhibited a 12.3 % burst release on day 1, and 85.8 % of the drug had been released after 30 days. The in vivo tests revealed a higher local drug concentration at the target lobe of the liver than at the adjacent median lobe. In the first week, the DOX concentration in the peripheral blood of the MS group was lower than that of the direct DOX injection group. Based on the measured intrahepatic concentration and plasma pharmacokinetic profiles, DOX-PLGA MSs could be suitable vectors of chemotoxic agents for intratumoral injection.

中文翻译：

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使用电喷雾法制备阿霉素负载的聚乳酸-聚乙二醇酸微球，并进行体外/体内评估，以实现持续的药物输送和潜在的肿瘤内注射。

对于癌症治疗，肿瘤内药物注射具有许多局限性并且不被普遍采用。聚[乳酸-乙醇酸共聚物]（PLGA）已经成为增强各种药物的体内/体外特性的有前途的载体。我们使用电喷雾方法制备了阿霉素-PLGA微球（DOX-PLGA MS）。采用体外洗脱方法评估DOX从MS中的释放。我们在大鼠上进行了一项体内研究，其中我们将DOX-PLGA MS直接注射入肝脏。我们测量了肝脏和血浆中的DOX浓度，以评估局部保留和全身暴露。MS的平均直径为6.74±1.01μm。MS的体外DOX释放在第1天表现出12.3％的突发释放，并且30天后已经释放了85.8％的药物。体内测试显示，在肝脏的目标肺叶中，局部药物浓度高于相邻的中叶。在第一周，MS组外周血中的DOX浓度低于直接DOX注射组。根据测得的肝内浓度和血浆药代动力学曲线，DOX-PLGA MSs可能是适合肿瘤内注射的化学毒剂载体。