Dimensional Analysis of Electromagnetic Particle Transport in a Fluid Flow under an Electromagnetic Field inspired by Biomedical Applications
Creators: name: Heo, Wonseok
Publisher: name: Purdue University Graduate School
Year: 2022
Subjects: Fundamental and theoretical fluid dynamics
Bio-fluids
Computational methods in fluid flow, heat and mass transfer (incl. computational fluid dynamics)
Biomedical fluid mechanics
Particle physics
Engineering electromagnetics

description: This study, motivated by biomedical applications such as drug delivery and adsorption, is aimed at describing magneto- and dielectro-phoretic systems via dimensional analysis to quantitatively assess the relative contribution of hydrodynamics, electromagnetism, and particle dynamics. Magnetophoresis and dielectrophoresis, phenomena of magnetic and dielectric particle transports, respectively, have been used in various applications requiring selective collecting or separating magnetic particles, especially in microfluidic systems. A multiphysics computational model for a magnetophoretic system was developed to assess magnetophoretic characteristics. The magnetically induced mobility of the magnetic particles was simulated for a range of parameters relevant in biomedical applications, including the particle and fluid properties, fluid velocity, and geometries of the particle, flow channel, and magnet. With the help of dimensional analysis, dimensionless numbers were introduced to reduce the number of parameters characterizing the transport of the particles suspended in an electrically non-conducting fluid exposed to an external magnetic field. As a result, 14 relevant variables determining the particle capture were reduced to only 3 dimensionless numbers describing the magnetophoretic system. The results from multiphysics models supported this analysis, suggesting a scaling law. The functional relationship among the dimensionless numbers resulted in prediction curves to assess the particle capture. The performance of the magnetophoretic system predicted with the dimensional analysis was verified in comparison with the available experimental data. In addition, the dimensionless numbers introduced here were compared with established numbers in magnetohydrodynamics (MHD). These theoretical and parametrical analyses of the magnetophoretic system were applied to the novel magnetic filter proposed to capture the drug-loaded small magnetic particles (MPs) from the bloodstream during the Intra-Arterial Chemotherapy (IAC). The IAC is a preferred treatment for unresectable hepatocellular carcinoma (HCC), the primary liver cancer. In the IAC procedure, chemotherapeutic agents, e.g. doxorubicin (Dox), are administered via a catheter placed in an artery supplying the tumor. The effectiveness of the IAC, however, is limited due to the passage of excessive chemotherapy agents to the blood circulation after their effect on the tumor, causing systemic toxicity. To remove the excessive drugs, the endovascular filtration devices have been developed. The proposed magnetic filtration device could be deployed from a catheter placed in the hepatic vein or inferior vena cava (IVC) to remove the excessive Dox from the bloodstream. The Ferumoxytol approved by the FDA is one of the types of the ultrasmall superparamagnetic iron oxide (USPIO) particles. The excessive Dox-coated USPIO can be filtered by a magnetic catheter-based device generating an external magnetic field. The filter utilizing magnetic fields is a promising method for therapeutic applications since an influence of magnetic field reaches comparatively wide ranges and magnetic fields do not affect biological tissues. To optimize the design, efficacy, and performance of the proposed magnetic filtration device, numerical models were developed based on the proposed dimensionless numbers characterizing drug transport and binding. Drug adsorption can be optimized by modifying magnetic field distribution and device configuration. To enhance the filtering up to 70-80 % of the excessive drug, multi-stage filters were developed by optimizing magnet configuration and flow patterns. By decreasing the concentration of toxins in the cardiovascular system, the drug dosage can be increased while reducing side effects, thus improving the effectiveness of the IAC treatment. In addition, new dimensionless numbers for dielectrophoresis analogous to magnetophoresis were introduced for a range of applications. The proposed dimensionless numbers for dielectrophoresis were evaluated for several conditions and compared with the previously established numbers in electrohydrodynamics (EHD). This study provides a promising framework for analyzing and predicting performance of various magneto- and dielectro-phoretic systems for a range of applications, particularly in biomedicine such as –drug filtering, targeted drug delivery, or small particle separation–, thus providing a reliable methodology for predicting particle manipulation.