Antiferromagnetic nanodiscs with perpendicular magnetic anisotropy for biological applications

Abstract Magnetic particles have been widely implemented across research areas in liquid and biological environments, such as cancer therapy, drug delivery and cell sorting. Perpendicularly magnetised (PM) synthetic antiferromagnetic (SAF) particles exhibit a range of desirable properties that make them strong candidates for applications in fluid. These include a zero remanence state, sharp and tunable switching, and a high and variable saturation magnetisation. Abstract This thesis will first continue to explore the flexibility of the SAF particle design. Through engineering of the SAF thin film, the basis of the particles, this work demonstrates the ability to tune the SAFs towards a suite of applications. In addition, a novel take on the fabrication of thin film based magnetic nanoparticles is presented. This method is capable of efficient and effective production of particularly high yields of well-defined nanodiscs with robust magnetic properties. Abstract The magnetic behaviour of the PM SAF particles, and the thin films they are created from, is analysed with particular focus on the characteristics displayed in a fluidic environment. This leads to the discovery of novel magneto-mechanical transitions of SAF particles in liquid and continues to demonstrate the applicability of SAFs across a spectrum of applications. Abstract Application of the PM SAF particles is examined in the context of cancer therapy. Previous studies into SAFs in cancer therapy utilised them in the magneto-mechanical destruction of tumour cells. Leading on from this work, the concept of integrating SAF microdiscs with iron oxide nanoparticles (IONPs) in a ‘magnetic combination therapy’ is explored. This preliminary study reveals interesting inter-particle interactions between the SAFs and IONPs and shows the potential for a synergistic effect in the combined therapy. Abstract This work provides a robust toolbox for the fabrication of tailored nanodiscs for use in a range of fluidic and biological applications.

Name dc:type.qualificationname

Doctor of Philosophy (PhD)

Level dc:type.qualificationlevel

Doctoral

Grantor dc:publisher.institution

University of Cambridge

Year dc:date.issued

2020

Author dc:creator

• Welbourne, Emma

Advisor dc:contributor.advisor

• Cowburn, Russell

• nanoparticles
• magnetism
• synthetic antiferromagnets
• perpendicular magnetic anisotropy
• biological applications

Licence

• https://www.repository.cam.ac.uk/bitstreams/d178de12-ea5b-4cb0-af21-2e04d6f6d341/download
• https://www.rioxx.net/licenses/all-rights-reserved/

Language dc:language

eng

Author Identifier

0000-0001-7328-4591

OAI identifier oai:identifier

oai:www.repository.cam.ac.uk:1810/323792