Engineers at the University of Tokyo have developed an electronic device that can closely monitor working heart cells without negatively affecting their natural behavior. The electronic nanomesh sensor is engineered in such a way that it can be in direct contact with the tissue. The results of their study was recently published in Nature.
"When researchers study cardiomyocytes in action they culture them on hard petri dishes and attach rigid sensor probes. These impede the cells’ natural tendency to move as the sample beats, so observations do not reflect reality well,” said Sunghooon Lee, researcher at the University of Tokyo. “Our nanomesh sensor frees researchers to study cardiomyocytes and other cell cultures in a way more faithful to how they are in nature. The key is to use the sensor in conjunction with a flexible substrate, or base, for the cells to grow on."
From the University of Tokyo article: "To make the sensors, first a process called electro-spinning extrudes ultrafine polyurethane strands into a flat sheet, similar to how some common 3D printers work. This spiderweb like sheet is then coated in parylene, a type of plastic, to strengthen it. The parylene on certain sections of the mesh is removed by a dry etching process with a stencil. Gold is then applied to these areas to make the sensor probes and communication wires. Additional parylene isolates the probes so their signals do not interfere with one another.
With three probes, the sensor reads voltage present at three locations. The readout appears familiar to anyone who’s watched a hospital drama as it’s essentially a cardiogram. Thanks to the multiple probes, researchers can see propagation of signals, which result from and trigger the cells to beat. These signals are known as an action or field potential and are extremely important when assessing the effect of drugs on the heart."
Read more about the electronic device that monitors heart cells at the University of Tokyo.