Doxorubicin is a drug used in treatments for cancer patients during chemotherapy.  However, due to whole body side effects such as killing fast growing cells, causing hair loss, and damaging the heart, doxorubicin is primarily of interest for targeted drug delivery.  By loading doxorubicin in porous nanoparticles with iron oxide cores, the magnetic properties of the nanoparticles can be used to direct the drug to the target area within the body.  This summer I worked in the lab of Dr. Sarah Larsen, in the Department of Chemistry, which specializes in the biomedical and environmental effects of porous nanomaterials.  The first phase of my project was the completion of the nanoparticle library.  The experimental conditions for the synthesis of Fe₃O₄@MCM-41 particles were calibrated to prepare mesoporous silica particles which have an average size of less than 100 nm and relative standard deviation less than 25%.  These nanoparticles have a hexagonally ordered pore structure (MCM-41) and a magnetite core (Fe₃O₄).

The second phase of my project involved cell studies on the following previously prepared particles:

• Fe₃O₄

• WO-SiO₂ (“wormhole” silica, a disordered interconnected pore structure)

• MCM-41

• Fe₃O₄@WO-SiO₂

MTS assays, a colorimetric test of cellular metabolic activity were used to assess the cytotoxicity of the particles, alone and loaded with doxorubicin, on A549 human lung carcinoma cells.  Controls show that the particles themselves were relatively non-toxic (cell viability approximately 90% for each type).  Loading the particles with doxorubicin resulted in a 5-15% decrease in cell viability.