Personal Information and Interests

Education:
M.S. Chemical Engineering Practice
Massachusetts Institute of Technology, 2001

M.S. Chemical Engineering
Massachusetts Institute of Technology, 2001

B.S. Chemical Engineering
University of Florida, 1999

Academic Interests

Research Interests: Magnetophoresis in Magnetic Fluids
Thesis Advisors: Alan Hatton, Kenneth A. Smith

Research Description

Magnetic fluids, also known as ferrofluids, consist of nano-sized, single-domain magnetic particles suspended in a liquid carrier. Surfactants or polymer layers are used to stabilize the magnetic particles and prevent agglomeration. In this research, we use a magnetic fluid consisting of magnetite nanoparticles (~ 10 nm in diameter) coated with a layer of PEO (~ 25 nm in total diameter, magnetite plus polymer) suspended in water. This is a very environmentally-friendly ferrofluid which can be used for biological applications.

One of the numerous features of magnetic fluids is that they can attain a "magnetic pressure" when subjected to an external magnetic field. Gradients in this magnetic pressure, resulting from gradients in the applied magnetic field, will result in magnetophoretic forces on other species suspended in the ferrofluid if these species have magnetizations different from that of the ferrofluid. This effect is analogous to the effect of hydrostatic pressure gradients in nonmagnetic fluids, where buoyancy forces will act on particles having specific gravities different from that of the fluid. In this research, we study the migration of nonmagnetic particles in magnetic fluids in the presence of time and space varying external magnetic fields. This is done both experimentally using fluorescence imaging and theoretically using the concepts of irreversible thermodynamics. Among other things, we study the effects of different time and space variations in applied magnetic fields and how these can be used for potential size-based separation of nonmagnetic species of both biological and non-biological origin.