Mathematical modeling and analysis of magnetic nanoparticle- induced heating in cerebrospinal fluid flow using a core-shell Fe3O4@Au nanoparticles for targeted drug therapy.

BACKGROUND: Neurological disorders often require effective delivery of therapeutic agents to specific regions of the central nervous system. Magnetic nanoparticles have emerged as a promising approach for improving targeted drug delivery through cerebrospinal fluid (CSF) under externally applied magnetic fields. However, the combined effects of porous media, magnetic forces, nanoparticle transport, and magnetic heating on CSF flow remain insufficiently understood.

METHODS: In this study, a mathematical model is developed to investigate the flow and heat transfer characteristics of CSF containing Fe3O4@Au magnetic nanoparticles in a porous channel. The Brinkman--Darcy framework is employed to describe the flow, while magnetic body forces are incorporated through the Kelvin force model. Heat generation arising from the magnetic response of nanoparticles is included in the energy equation. The governing equations are transformed into dimensionless form and solved analytically using a perturbation technique to obtain expressions for velocity, temperature, volumetric flow rate, wall shear stress, and Nusselt number.

RESULTS: The analysis reveals that increasing permeability, Reynolds number, and magnetic interaction parameter enhances the velocity and volumetric flow rate of the nanofluid. In contrast, increasing nanoparticle volume fraction reduces fluid velocity due to the associated increase in effective viscosity. Temperature is found to increase significantly with magnetic heating, while higher thermal conductivity promotes heat diffusion and reduces thermal accumulation. The wall shear stress follows trends similar to velocity, increasing with permeability, Reynolds number, and magnetic forces. The Nusselt number is strongly influenced by magnetic heating and thermal conductivity, highlighting the competing effects of heat generation and heat diffusion.

DISCUSSION AND CONCLUSION: The results demonstrate the significant role of magnetic forces, porous medium properties, and nanoparticle characteristics in controlling CSF transport and thermal behavior. The proposed model provides insight into the transport and distribution of magnetic nanoparticles in CSF and may contribute to the design and optimization of magnetically guided drug delivery systems for neurological applications.