Field-Free Region Scanning-Based Magnetic Microcarrier Targeting in Multibifurcation Vessels

Abstract

Navigation of microcarriers in complex environments as a vascular network remains an open challenge due to limited solutions for effective targeting strategy. Simultaneous real-time visualization and manipulation of microcarriers at any depth in the human body is far to be achieved even though one of each task has been successfully proven. Herein, a novel targeting strategy is proposed that employs field-free region (FFR) scanning to guide microcarriers through multiple bifurcations within a predefined vessel network. The main challenge of this method lies on how, where, and when to activate FFR to steer a particle to a desired direction, regardless of its spatial feedback. To achieve it, first, a mathematical model of particle motion in a vessel network is developed to predict particle behaviors and positions. Subsequently, an optimization algorithm is formulated to place FFR well-coordinated around each bifurcation at a designated moment. The established solution for targeting a magnetic microcarrier is preemptively evaluated through finite element simulations and then successfully implemented in in vitro multibranched vessels. © 2024 The Authors. Advanced Intelligent Systems published by Wiley-VCH GmbH.