Micro magnetofluidics : interactions between magnetism and fluid flow on the microscale.

Abstract

Micro-magnetofluidics refers to the science and

technology that combines magnetism with microfluidics to

gain new functionalities. Magnetism has been used for

actuation, manipulation and detection in microfluidics. In

turn, microfluidic phenomena can be used for making tunable

magnetic devices. This paper presents a systematic

review on the interactions between magnetism and fluid flow

on the microscale. The review rather focuses on physical and

engineering aspects of micro-magnetofluidics, than on the

biological applications which have been addressed in a

number of previous excellent reviews. The field of micromagnetofluidics

can be categorized according to the type of

the working fluids and the associated microscale phenomena

of established research fields such as magnetohydrodynamics,

ferrohydrodynamics, magnetorheology and magnetophoresis.

Furthermore, similar to microfluidics the field can

also be categorized as continuous and digital micro-magnetofluidics.

Starting with the analysis of possible magnetic

forces in microscale and the impact of miniaturization on

these forces, the paper revisits the use of magnetism for

controlling fluidic functions such as pumping, mixing,

magnetowetting as well as magnetic manipulation of particles.

Based on the observations made with the state of the art

of the field micro-magnetofluidics, the paper presents some

perspectives on the possible future development of this field.

While the use of magnetism in microfluidics is relatively

established, possible new phenomena and applications can

be explored by utilizing flow of magnetic and electrically

conducting fluids.