Surface modifications of iron oxide nanoparticles for biological applications

Iron oxides magnetic nanoparticles (MPs) of high crystallinity, high magnetization, and size-monodispersity were synthesized with oleic acid as their native ligands. These hydrophobic and non-functionalized MPs have magnetic properties that are suitable for various biological applications. Surface modifications were studied for transferring these MPs into biological environments as well as transforming them into functional nanoparticles. Certain surface modifications of MPs, such as attaching silane groups and silica coating, lead to formation of more complex structures of superparamagnetic and fluorescent silica microspheres and nanostructures. These microspheres and nanostructures comprising MPs and semiconductor quantum dots (QDs) are useful tools for biological applications such as for magnetically controlling with fluorescent tracking of particles and for bimodal imaging. Surface modifications of MPs with hydrophobically-modified polyacrylic acid (mPAA) amphiphilic polymer and catechol-derivative surfactants resulted in hydrophilic MPs that are stable in physiological environment and small in their hydrodynamic size. These MPs are also designed to possess active functional groups that are necessary for further conjugations with proteins and molecules of interest. These hydrophilic and functional MPs are useful in biological applications such as magnetic resonance imaging and sensing applications.

Department dc:contributor.department

Massachusetts Institute of Technology. Dept. of Chemistry.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2011

Author dc:creator

• Insin, Numpon

Advisor dc:contributor.advisor

• Moungi G. Bawendi.

• Chemistry.

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/62723

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/62723