Drug delivery plays a substantial role in a more effective treatment of diseases of the central nervous system; therefore, the selection of an appropriate drug carrier system is very important to enhance the effectiveness of drugs. Due to the effect of surfactant on improvement of polymer performance in drug-carrying systems, the present study was devoted to investigating the influence of Polysorbate 80 (Pst80) surfactant on poly( n -butylcyanoacrylate)(PBCA)/Tacrine and Chitosan/Tacrine drug-carrying systems from molecular point of view. Interaction energy, structural characterization, Flory–Huggins interaction parameter, and solvation free energy were investigated for both systems by employing molecular dynamics simulations. According to the interaction energy and Flory–Huggins parameter results, Pst80 can be a more suitable choice for targeted releasing of drug in PBCA/Tacrine system compared with Chitosan/Tacrine system because Pst80 firmly surrounded the drug carrier PBCA and Tacrine. Additionally, the solvation free energy results demonstrated more solubility of PBCA/Pst80/Tacrine in water medium compared with that of Chitosan/Pst80/Tacrine. By consideration on different solvation free energy contributions, it was concluded that using a polymer with both hydrophilic and hydrophobic parts, presence of functional groups with heavy atoms on both polymer and surfactant and similarity in chemical nature of hydrophobic parts of both polymer and surfactant can be useful approaches to reduce the total solvation free energy. Preparation of an appropriate solubility of polymer/drug in water/surfactant medium is essential to enhance drug delivery system efficiency and reduce waste of drug in human body, which can be achieved by designing a drug-carrying system with the minimum solvation free energy. This study confirms the significant role of molecular dynamics simulation for a detailed study of polymer/surfactant/dug systems and clarifies its effective role for designing novel drug delivery systems, along with saving time and cost.

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聚合物/表面活性剂系统中药物分子包封过程的新见解：分子模拟研究

药物递送在更有效地治疗中枢神经系统疾病方面发挥着重要作用；因此，选择合适的药物载体系统对于提高药物的有效性非常重要。由于表面活性剂对提高聚合物载药系统性能的影响，本研究致力于研究聚山梨醇酯80（Pst80）表面活性剂对聚（正丁基氰基丙烯酸酯）（PBCA）/他克林和壳聚糖/他克林药物的影响。 - 从分子的角度来看携带系统。通过分子动力学模拟研究了两个系统的相互作用能、结构表征、弗洛里-哈金斯相互作用参数和溶剂化自由能。根据相互作用能和 Flory-Huggins 参数结果，与壳聚糖/他克林系统相比，Pst80 可以成为 PBCA/他克林系统靶向释放药物的更合适的选择，因为 Pst80 牢固地包围了药物载体 PBCA 和他克林。此外，溶剂化自由能结果表明，与壳聚糖/Pst80/他克林相比，PBCA/Pst80/他克林在水介质中的溶解度更高。通过考虑不同的溶剂化自由能贡献，得出结论：使用具有亲水和疏水部分的聚合物，聚合物和表面活性剂上都存在具有重原子的官能团以及聚合物和表面活性剂疏水部分的化学性质相似可以是减少总溶剂化自由能的有用方法。制备合适的聚合物/药物在水/表面活性剂介质中的溶解度对于提高药物递送系统效率和减少药物在人体内的浪费至关重要，这可以通过设计具有最小溶剂化自由能的载药系统来实现。这项研究证实了分子动力学模拟在详细研究聚合物/表面活性剂/药物系统方面的重要作用，并阐明了其在设计新型药物递送系统以及节省时间和成本方面的有效作用。