Fabrication And Characeterization Of Granular Magnetic Gold Nanoparticles

In recent years, gold and magnetic nanoparticles have showed great potential in biomedical applications. Magnetic nanoparticles can be used in both in- vivo and in-vitro applications such as drug and gene delivery, hyperthermia treatment of cancer, MRI contrast enhancement, cell labeling and magnetic separation. Due to the surface plasmon resonance effect (SPR), gold nanoparticles strongly absorb and scatter visible and infrared light in resonance with SPR. They have been exploited for bioimaging and photothermal therapy applications. This is why different sizes and shapes of Au nanoparticles exhibit different colors.In this thesis, we are investigating a new type of nanoparticles, granular magnetic Au particles. The particle size ranges from 10nm to 200nm. These nanoparticles have the potential to combine the properties of both gold nanoparticle and the magnetic nanoparticle into one nano entity to provide multifunctionality. . For example, magnetic Au nanoparticles can be concentrated to a tumor sites by an external magnetic field gradient and photothermal therapy can be performed to locally kill tumor cells. A scalable, straight forward and inexpensive process using electrochemical deposition is being developed to produce these multifunctional nanoparticles.On a polycarbonate template, multilayers of gold and cobalt were deposited through electrodeposition. The deposition time of both gold and cobalt were varied to manipulate the thickness to achieve the superparamagnetic property. Before depositing the multilayers, gold, cobalt or copper was used as a sacrificial layer. The magnetic properties were measured using AGM or VSM. The structural properties were characterized through SEM and TEM.