Impact of Array Length on Particle Attraction in Magnetic Drug Targeting: Investigation Using an Exponential Approximation of the Magnetic Field

In magnetic drug targeting, special magnetic nanoparticles that carry the anticancer drug are injected into the cardiovascular system in the vicinity of the tumor and are navigated into the tumor using a magnetic field. Many researchers optimize single magnets for this purpose; however, magnetic arrays that are placed parallel to the vessel in order to increase the impact time of the magnetic force on the particles are also discussed. To the best of the authors' knowledge, the improvement by the increased impact time has not been studied in detail so far and, thus, will be addressed in this work. In this context, an artificial exponential magnetic field that approximates the field of a Halbach array and acts as an upper limit consideration is applied to different impact lengths within a predefined magnetic domain. To compare the impact of the field parameters, the total magnetic energetic effort is kept constant as a reference for studying variations of impact length. The results reveal that a longer impact length increases the attraction performance enormously. However, for the same magnetic effort, a longer impact length with a lower magnetic field strength leads to the same attraction of the particles as a shorter one with higher field strengths. Since it is easier to generate lower field strengths, the usage of arrays to realize a longer impact length is preferable.