Predictive Modeling and Experimental Validation of Magnetophoretic Delivery of Magnetic Nanocultures.

Magnetophoresis offers a powerful strategy for the targeted delivery of functional microcapsules. Here, we present a combined theoretical and experimental framework to predict the magnetophoretic transport of magnetic nanocultures-microcapsules embedded with magnetic nanoparticles and living cells. We derive a novel analytical expression for the terminal velocity of microcapsules under a spatially decaying magnetic field. The model incorporates magnetic and hydrodynamic forces in low Reynolds number regimes and predicts microcapsule velocity variations with nanoparticle size and field strength. Experimental validation using nanocultures containing nanoparticles 5, 10, and 20 nm in size confirms the model's accuracy, with 10-nm particles showing optimal magnetophoretic response. The model also accounts for hindered motion at high microcapsule densities. This work provides a predictive tool for designing magnetically guided systems for microbial delivery, localization, and patterning, with applications in bioreactors, therapy, and engineered living materials.