Uniform magnetic targeting of magnetic particles attracted by a new ferromagnetic biological patch

Abstract

A new non-toxic ferromagnetic biological patch (MBP) was designed in this paper. The MBP consisted of two external layers that were made of transparent silicone, and an internal layer that was made of a mixture of pure iron powder and silicon rubber. Finite-element analysis showed that the local inhomogeneous magnetic field (MF) around the MBP was generated when MBP was placed in a uniform MF. The local MF near the MBP varied with the uniform MF and shape of the MBP. Therefore, not only could the accumulation of paramagnetic particles be adjusted by controlling the strength of the uniform MF, but also the distribution of the paramagnetic particles could be improved with the different shape of the MBP. The relationship of the accumulation of paramagnetic particles or cells, magnetic flux density, and fluid velocity were studied through in vitro experiments and theoretical considerations. The accumulation of paramagnetic particles first increased with increment in the magnetic flux density of the uniform MF. But when the magnetic flux density of the uniform MF exceeded a specific value, the magnetic flux density of the MBP reached saturation, causing the accumulation of paramagnetic particles to fall. In addition, the adsorption morphology of magnetic particles or cells could be improved and the uniform distribution of magnetic particles could be achieved by changing the shape of the MBP. Also, MBP may be used as a new implant to attract magnetic drug carrier particles in magnetic drug targeting. Bioelectromagnetics. 39:98-107, 2018. © 2017 Wiley Periodicals, Inc.

Biodistribution, biocompatibility and targeted accumulation of magnetic nanoporous silica nanoparticles as drug carrier in orthopedics

“…In stent models with a magnetic source inside the vessel as well as in investigations towards particle behavior in a vessel with close externally applied magnetic field (simulation or in vitro, respectively) the following proportionalities were observed: The higher the magnetic field strength and the gradient, the particle size and concentration and the lower the fluid flow velocity and the distance between vessel and external magnet, the higher the capture efficiency of the magnet [50,85,86,[105][106][107][108]. In the here presented study, magnetic field application time of 10 min might have been too short 54] or the produced magnetic field strength was insufficient [77,[109][110][111] although many in vitro and in vivo studies used lower magnetic field strength than 1.7 T for successful targeting [43,60,85].…”