Numerical analysis of capture and isolation of magnetic nanoparticles in microfluidic system

Rapid capturing and isolation of magnetic nanoparticles is critical for microfluidic biodetection system. A numerical model based on multiphysics coupled-field finite-element method is developed for evaluating the capture and segregation of magnetic nanoparticles in microfluidic channel. The model consists of microfluidic channels surrounded by four electromagnets changed periodically. The trajectories and trapping efficiencies are numerically analyzed for multiple magnetic nanoparticles released in microfluidic channel. Simulation results showed that magnetic pole current, inlet velocity and diameter of magnetic nanoparticles have an impact on the capture efficiency of magnetic nanoparticle. Thus, the model with the optimal parameters can reasonably predict and evaluate completely trapping of 180 nm magnetic nanoparticles in the simulation. The numerical analysis will encouraging for the design and development of new microfluidic bioseparation and detection microsystems.