Exploring Controlled Drug Release from Magneto-Liposomes using Ultrsound Generation by High Frequency Pulsed Magnetic Fields.

Kansas State University, Manhattan KS

Investigators

Abstract

The proposed work investigates how sound waves from the combination of tiny magnetic particles and magnetic fields can be utilized to provide efficient delivery of small drug molecules. This experimental approach has a potential to carry out task deep inside the human body in a very fast manner compared to existing technology. The objective of the research is to explore the precise underlying physics and chemistry that controls the effectiveness of this proposed drug delivery methodology and push its limits to be able to engineer a practical medical device. How much of this ultrasound can be generated and how the magnetic particles need to be placed for effective drug delivery will be addressed in this work. The proposed work will provide unique training opportunity to undergraduate and graduate research assistants in theoretical and experimental tools of multidisciplinary fields of chemistry, physics, and medical sciences. The key objective of the proposed research is to assess the drug delivery capability of a new improved magneto-liposome structure that aims at addressing the shortcomings of previous magneto liposome designs. In this new magnetic liposome structure, gold coated iron oxide nanoparticles will be used as a source of ultrasound for triggering drug delivery in the liposomes. The gold surface of the magnetic particles facilitates a strong attachment of chemical linker via thiol functional groups. The magnetic structures that produce local ultrasonic vibrations are attached to the liposomes via thiolated polyethylene glycol derivatives of cholesterol and phospholipids. As a secondary objective of the proposed research, the PI aims at exploring a potentially more efficient ultrasound generation process from non-spherical magnetic nanorods in rotating magnetic fields. The proposal describes a pulsed magnet capable of mechanically turning colloidal nanostructures. A course-grained molecular dynamics simulation will be developed to provide physical insight into the mechanism of ultrasound generation in colloidal magnetic solutions. It has been found recently that colloidal magnetic nanostructures are able to produce sufficiently large amount of ultrasound that can induce drug release in magneto liposomes from high frequency magnetic fields. The key hypothesis is that once the magnetic particles are moved outside the liposomes structures, one can trigger more efficient drug release, and can carry larger drug delivery capacity from the same sized magneto liposomes when compared to previous designs. It is anticipated that the drug molecules from the liposomes can be released in a very short time (sub millisecond timescale) without significant temperature rise, which will create a new platform for practical delivery of short lived temperature sensitive drug molecules. The proposed work also addresses ultrasound generation in different ways compared to the previous discoveries. It is hypothesized that ultrasound may be generated from anisotropic magnetic nanostructures (nanorods) more effectively in rotating magnetic fields than from spherical magnetic particles in inhomogeneous non-rotating magnetic fields.