Targeted Magnetic Nanoparticles for Remote Magnetothermal Disruption of Amyloid-beta Aggregates

TitleTargeted Magnetic Nanoparticles for Remote Magnetothermal Disruption of Amyloid-beta Aggregates
Publication TypeJournal Article
Year of Publication2015
AuthorsLoynachan, CN, Romero, G, Christiansen, MG, Chen, R, Ellison, R, O'Malley, TT, Froriep, UP, Walsh, DM, Anikeeva, PO
JournalAdvanced Healthcare Materials
Volume4
Issue14
Pagination2100 - 2109
Date Published2015/10/07/
Abstract

Remotely triggered hysteretic heat dissipation by magnetic nanoparticles (MNPs) selectively attached to targeted proteins can be used to break up self-assembled aggregates. This magnetothermal approach is applied to the amyloid-beta (A beta) protein, which forms dense, insoluble plaques characteristic of Alzheimer's disease. Specific targeting of dilute MNPs to A beta aggregates is confirmed via transmission electron microscopy (TEM) and is found to be consistent with a statistical model of MNP distribution on the A beta substrates. MNP composition and size are selected to achieve efficient hysteretic power dissipation at physiologically safe alternating magnetic field (AMF) conditions. Dynamic light scattering, fluorescence spectroscopy, and TEM are used to characterize the morphology and size distribution of aggregates before and after exposure to AMF. A dramatic reduction in aggregate size from microns to tens of nanometers is observed, suggesting that exposure to an AMF effectively destabilizes A beta deposits decorated with targeted MNPs. Experiments in primary hippocampal neuronal cultures indicate that the magnetothermal disruption of aggregates reduces A beta cytotoxicity, which may enable future applications of this approach for studies of protein disaggregation in physiological environments.