Improving drug delivery to a specific site of body is an important issue. Magnetic drug targeting is an appropriate technique for drug delivery to a specified area. This method has been adopted in drug delivery to the lung tissues due to widespread outbreak of the lung cancer in the recent decades. Therefore, increasing the efficiency of drug delivery to the lung tissues is of paramount importance. In this article, controlled particle release from a determined area and magnetic drug targeting methods are used to deliver the drug to a tumor in the generation G2 of the human lung. Weibel model is used for modeling of the human lung airways, and particles are made of iron oxide magnetic cores and poly lactic coglycolic acid shell. Herein, two different methods of drug delivery are tested and compared. In the first method, controlled particle release in the absence of magnetic field is accomplished and in the second method, controlled particle release in the presence of magnetic field is performed for the first time. A coil is used to produce magnetic field. Comparison of the results obtained in this article with the previous results of the drug delivery to tumors by random particle release method (in the presence and absence of magnetic field) showed that controlled particle release method improves the deposition efficiency on the tumor surface and increases the efficiency from 0.09% (random particle release in the absence of magnetic field) and 5.69% (random particle release in the presence of magnetic field) for tumor with r/R = 1.5 to 87% and 100% in the controlled particle release without and with the presence of magnetic field, respectively. Consequently, the best method of drug targeting is controlled particle release in the presence of the magnetic field. Using the mentioned method, deposition efficiency reaches 100% for tumors with r/R values of 0.5, 1, and 1.5 in this article.

中文翻译：

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用于人肺中药物递送的磁性粒子的受控释放

改善向身体特定部位的药物递送是一个重要问题。磁性药物靶向是将药物递送到指定区域的合适技术。由于近几十年来肺癌的广泛爆发，这种方法已被用于将药物递送到肺组织。因此，提高药物输送到肺组织的效率至关重要。在这篇文章中，通过确定区域的受控颗粒释放和磁性药物靶向方法，将药物输送到人肺 G2 代的肿瘤中。Weibel模型用于人体肺气道的建模，颗粒由氧化铁磁芯和聚乳酸共乙醇酸壳构成。在此，测试和比较了两种不同的给药方法。在第一种方法中，实现了无磁场下的颗粒控释，第二种方法是首次进行了有磁场的颗粒控释。线圈用于产生磁场。本文获得的结果与之前通过随机粒子释放方法（有磁场和无磁场）将药物递送至肿瘤的结果进行比较表明，受控粒子释放方法提高了在肿瘤表面的沉积效率并增加了肿瘤的效率从 0.09%（无磁场下的随机颗粒释放）和 5.69%（有磁场的随机颗粒释放），r/R = 1.5 到 87% 和 100%分别与磁场的存在。最后，药物靶向的最佳方法是在磁场存在下控制粒子释放。使用上述方法，本文中 r/R 值为 0.5、1 和 1.5 的肿瘤的沉积效率达到 100%。