Homogeneous chitosan nanoparticles utilizing EPR effect and pH-sensitive properties have an immense potential for loading and delivery of anticancer drugs. The aim of this study was preparing doxorubicin-loaded homogeneously distributed chitosan nanoparticles by using a simple and mild method, modified ionic gelation, with a very high encapsulation efficiency for controlled and pH-sensitive release. FESEM image revealed that the synthesized chitosan nanoparticles had a uniform spherical morphology with the size range 20–35 nm. The parameters of drug stirring duration, drug amount and nanoparticles formation time were changed to achieve maximum encapsulation efficiency as well as the effect of each parameter on the encapsulation efficiency was studied. The encapsulation efficiency toward doxorubicin under optimal conditions was 81.6±0.8 % (n=5±SD) that was higher than those previously published in literature. The investigations of doxorubicin release from chitosan nanoparticles in four media with different pH values showed a pH-sensitive release with a higher release rate in an acidic environment. The drug release mechanism at all pH values was also evaluated by zero-order, first-order, Higuchi and Korsmeyer-Peppas models. The most consistent model for release curve at four pHs was Korsmeyer-Peppas model. Therefore, we presented a method for the preparation of homogeneous doxorubicin-loaded chitosan nanoparticles with small size that can be industrialized because they were made based on a very simple and green method without the use of a complex system and expensive materials as well as due to their high encapsulation efficiency.

利用EPR效应和pH敏感特性的均相壳聚糖纳米粒子具有巨大的潜力来装载和输送抗癌药物。这项研究的目的是通过使用简单温和的方法，修饰的离子凝胶法以及对控制和pH敏感的释放具有非常高的封装效率的方法，制备负载阿霉素的均匀分布的壳聚糖纳米颗粒。FESEM图像显示合成的壳聚糖纳米颗粒具有均匀的球形形态，尺寸范围为20-35 nm。改变药物搅拌时间，药物量和纳米颗粒形成时间的参数以达到最大包封效率，并研究了各个参数对包封效率的影响。在最佳条件下对阿霉素的包封率为81.6±0。8％（n = 5±SD），高于先前文献中发表的那些。在四种具有不同pH值的介质中从壳聚糖纳米颗粒中释放阿霉素的研究表明，在酸性环境中，pH敏感的释放具有较高的释放速率。还通过零阶，一阶，Higuchi和Korsmeyer-Peppas模型评估了在所有pH值下的药物释放机理。在四个pH下最一致的释放曲线模型是Korsmeyer-Peppas模型。因此，我们提出了一种制备均一的，负载阿霉素的纳米粒壳聚糖纳米颗粒的方法，该方法可以工业化，因为它们是基于非常简单和绿色的方法制备的，无需使用复杂的系统和昂贵的材料，并且由于它们的高封装效率。