An intact blood-brain barrier is essential in order to maintain brain homeostasis and preserve neuronal function. However, its presence prevents over 98% of conventional small molecule drugs from entering the brain, making the treatment of brain diseases such as Alzheimer’s disease extremely challenging. Due to this, there has been great interest in designing methods to overcome the blood-brain barrier, but many of these are either highly invasive, non-targeted or show poor efficiency. Over the past twenty years, the use of focused ultrasound in combination with circulating microbubbles has emerged as a promising strategy, allowing the blood-brain barrier to be disrupted in a completely non-invasive, targeted and transient manner. In this thesis, we have developed two systems to take advantage of this technology: DNA-coated nanoparticles as potential delivery platforms for combination therapies and a series of metal complexes as potential inhibitors of amyloid beta aggregation for the treatment of Alzheimer’s disease. In Chapter 2, we began by synthesising a series of fluorescently-labelled DNA-coated nanoparticles and showed that they can be successfully delivered to a target location across the blood-brain barrier in mice using ultrasound. Ongoing work is seeking to evaluate drug-loaded derivatives of these nanoparticles in vitro and in vivo. In Chapters 3 and 4, a series of metal salphens and salnaphs were investigated for their ability to inhibit the aggregation of the amyloid beta peptide, which is one of the key hallmarks of Alzheimer’s disease. Through a series of in vitro assays, we showed that the synthesised metal complexes are able to inhibit amyloid beta aggregation and are non-cytotoxic. Using ultrasound-mediated blood-brain barrier opening methods, these complexes were successfully delivered into the brains of mice, allowing their therapeutic efficacy to be assessed in vivo. Preliminary findings obtained with our complexes in an Alzheimer’s disease mouse model are presented.