School of Mechanical Engineering, Shiraz University, Shiraz, Iran.
School of Mechanical Engineering, Shiraz University, Shiraz, Iran.
Comput Methods Programs Biomed. 2019 Apr;172:11-24. doi: 10.1016/j.cmpb.2019.02.001. Epub 2019 Feb 2.
Magnetic drug targeting improves effectiveness of medicine application and reduces its side effects. In this method, drugs with magnetic core are released in the lung and they are steered towards the tumor by applying an external magnetic field. A number of researchers utilized numerical methods to study particle deposition in the lung, but magnetic drug delivery to the tumors in the human lung has not been addressed yet.
In the present study, Weibel model is used for human airway geometry from generation G0-G3. Moreover, a tumor is considered in the lung, which is located in G2. Particles are made of iron oxide magnetic cores and poly lactic coglycolic acid shells. Fluid flow is assumed laminar and particles are coupled with the fluid by one-way method. The magnetic field is produced by a coil with law current intensities instead of a wire with high current intensities. Influences of various parameters such as particle diameter, magnetic source position, current intensity, and inlet mass flow rate and tumor size on the deposition efficiency on the tumor surface are reported.
Results show that magnetic drug targeting enhances deposition efficiency on the tumor surface Furthermore, when the current intensity rises from 10 (A) to 20 (A), tumor enlarging, and increasing particle diameter, lead to deposition efficiency enhancement, but efficiency decreases by increasing mass flow rate. However, when current intensity is 20 (A), deposition efficiency decreases in two situations. The first situation is when mass flow rate is 7 (L/min) and particle diameter is 9 (µm), and the second one is in 10 (L/min) mass flow rate and 9 (µm) diameter.
The results demonstrated that magnetic drug targeting is applicable and suitable for all tumors specially for small tumors (r/R = 0.5 in this case) that efficiency increase from 0% in the absence of magnetic field to more than 2% in the presence of magnetic field.
磁靶向药物输送可提高药物应用的效果并降低其副作用。在这种方法中，将具有磁性内核的药物释放到肺部，然后通过施加外部磁场将药物导向肿瘤。许多研究人员利用数值方法研究了肺部中的颗粒沉积，但尚未解决将药物输送到人体肺部中的肿瘤。
在本研究中，我们使用 Weibel 模型来生成 G0-G3 级别的人类气道几何形状。此外，在肺部中考虑了一个肿瘤，它位于 G2 级。颗粒由氧化铁磁核和聚乳酸-羟基乙酸外壳组成。假设流体流动为层流，并且通过单向方法将颗粒与流体耦合。磁场由具有法向电流强度的线圈产生，而不是由具有高电流强度的线产生。报告了各种参数（例如颗粒直径、磁源位置、电流强度、入口质量流速和肿瘤大小）对肿瘤表面沉积效率的影响。
结果表明，磁靶向药物输送可提高肿瘤表面的沉积效率。此外，当电流强度从 10（A）增加到 20（A）时，肿瘤增大和颗粒直径增加，导致沉积效率提高，但增加质量流速会导致效率降低。但是，当电流强度为 20（A）时，两种情况都会导致沉积效率降低。第一种情况是当质量流速为 7（L/min）且颗粒直径为 9（µm）时，第二种情况是在 10（L/min）质量流速和 9（µm）直径的情况下。
结果表明，磁靶向药物输送是可行且适用于所有肿瘤，特别是对于小肿瘤（在这种情况下，r/R=0.5），在没有磁场的情况下效率从 0%增加到 2%以上。
