Researchers from the Core Research for Evolutional Science and Technology project in Japan, led by Takehiko Kitamori of the University of Tokyo, have developed a miniaturized pump powered by heart cells for use on a chip.

The use of cells in microfluidic devices currently exploits biochemical function, but Kitamori has focused on mechanical properties. Sheets of heart cells (cardiomyocytes), which contract as the heart beats, have been harnessed to form chip-based actuators.  

Cellular systems often exhibit complex behaviour that is difficult to replicate, so researchers have long aimed to incorporate cellular systems into miniaturized total analysis systems. The volume of fluid required by the chips for these systems is roughly proportional to the size and processing capabilities of cardiomyocytes. Unlike conventional micropumps and micromotors, heart cells can be operated automatically using only glucose and oxygen as their power source, readily turning chemical to mechanical energy.

'The cell-based microchip pumping system [will] enhance fundamental concepts and designs of microfluidic devices,' said Kitamori. Cell-actuated microfluidic devices have potential for use in drug delivery systems whose flow rate varies as the device itself responds to local drug concentrations, according to the team. However, the tissue building blocks of the chip have a limited lifespan that will need to be extended before a practical chip can be built.

Suzanne Abbott