Abstract

Magnetic Nanofluids in Micro Devices

Raju Ramanujan, Professor, Nanyang Technological University

There is an urgent requirement for next generation microdevices, especially for lab-on-a-Chip applications. Magnetic nanofluids, i.e., magnetic nanoparticles suspended in carrier fluids, can be used to meet new, exacting performance standards. They exhibit several advantages for such applications, including wireless control, remote actuation, facile micromixing and harnessing the magnetoviscous effect and high shear environment for cell sorting. Our recent results show that the behavior of these fluids can be readily controlled by a single, uniform, low field strength, magnetic field. This is in contrast to most other studies, which focus on magnetic field gradient devices which are much more complex, bulky and expensive. We have performed both experimental and modeling studies on magnetofluidic spreading, fluid instabilities and biological entity concentration in microdevices. Excellent agreement between experiment and theory has been achieved, these results will be presented. The authors are grateful to the SERC, Singapore for financial support for this work through ASTAR PSF 2012 Project: 1321202078.