Optimized shapes of magnetic arrays for drug targeting applications. (4th May 2016)

• Record Type: Journal Article
• Authors: Barnsley, Lester C; Carugo, Dario; Stride, Eleanor
• Is Part Of: Journal of physics. Volume 49:Number 22(2016)
• Publication Date: 2016-05-04
• Subjects: magnetic drug targeting -- Halbach array design -- optimization -- magnetic nanoparticle -- permanent magnet flux source -- targeted drug delivery; Physics -- Periodicals; 530
• DOI: 10.1088/0022-3727/49/22/225501
• Languages: English
• ISSNs: 0022-3727

Abstract

Abstract: Arrays of permanent magnet elements have been utilized as light-weight, inexpensive sources for applying external magnetic fields in magnetic drug targeting applications, but they are extremely limited in the range of depths over which they can apply useful magnetic forces. In this paper, designs for optimized magnet arrays are presented, which were generated using an optimization routine to maximize the magnetic force available from an arbitrary arrangement of magnetized elements, depending on a set of design parameters including the depth of targeting (up to 50 mm from the magnet) and direction of force required. A method for assembling arrays in practice is considered, quantifying the difficulty of assembly and suggesting a means for easing this difficulty without a significant compromise to the applied field or force. Finite element simulations of in vitro magnetic retention experiments were run to demonstrate the capability of a subset of arrays to retain magnetic microparticles against flow. The results suggest that, depending on the choice of array, a useful proportion of particles (more than 10 % ) could be retained at flow velocities up to 100 mm s −1 or to depths as far as 50 mm from the magnet. Finally, the optimization routine was used to generate a design for a Halbach array optimized to deliver magnetic force to a depth of 50 mm inside the brain.