Surface Modifications of Iron Oxide Nanoparticles for Magnetic Imaging and Diagnosis

Contrast agents are commonly used in magnetic resonance imaging (MRI) for their ability to selectively highlight or darken image brightness from different tissue components depending on their chemical nature. This work explores and discusses potential of colloidal iron oxide nanoparticles as non-toxic MRI contrast agents for diagnosis. Novel single-nanometer iron oxide (SNIO) nanoparticles exhibited contrast enhancement in T1-weighted MRI superior than commercially used gadolinium-based contrast agents, with unprecedentedly fast and clean renal clearance in inorganic colloidal nanoparticles. An approach for size determination based on small-angle X-ray scattering (SAXS) was developed, and understanding of particle size distribution led to successful development of alkyne-functionalized nanoparticles allowing for conjugation with biological cargos, creating a novel vehicle for drug delivery. SNIO–CBP, product from conjugating functionalized SNIO nanoparticles with a nature-inspired cyclic collagen-binding peptide (CBP) through newly developed preparatory copper-catalyzed alkyne–azide coupling CuAAC, exhibited binding affinity towards type I collagen, a natural indicator of fibrosis abundant in the extracellular matrix. SNIO–CBP was able to quickly detect hepatotoxin-induced and diet-induced non-alcoholic steatohepatitis (NASH) in mice through T1-weighted MRI upon intravenous administration. New formulations of hydrophilic iron oxide nanoparticles were explored. Tailored for quantitative ultra-short time-to-echo contrast-enhanced (QUTE-CE) MRI, catechol-coated iron oxide with 10 nm mean diameter was optimized; carboxymethyl dextran as a new ligand system was developed on SNIO and formation of nanoparticle clusters was observed, implying its potential for the emergent preclinical technique of magnetic particle imaging (MPI).

Name thesis:degree_name

Doctoral

Department dc:contributor.department

Massachusetts Institute of Technology. Department of Chemistry

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2022

Author dc:creator

• Zhang, Juanye

Advisor dc:contributor.advisor

• Bawendi, Moungi G.

Statement dc:rights

• In Copyright - Educational Use Permitted
• Copyright MIT

Licence dc:rights.uri

• http://rightsstatements.org/page/InC-EDU/1.0/

Handle dc:identifier.uri

https://hdl.handle.net/1721.1/147443

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/147443