Scientists in the US have developed a new way of pumping ferrofluids without the use of any mechanical components. They claim that their technique, dubbed “ferrohydrodynamic pumping”, can be easily scaled up or down to be used in microfluidic devices or industrial-scale pumping devices, and anything in between.
Ferrofluids were developed by NASA in the 1960s as a way to non-mechanically pump fuel in space. They fall under the umbrella of “smart fluids” – fluids whose properties can be changed by applying a magnetic or electrical field. Today, ferrofluids have a wide range of applications, being used liquid 0-rings, in high-end audio speakers and computer circuitry, as well as biomedical devices.
More details here Ferrofluid pump has no moving parts