A team of engineers and scientists have developed a new sensor that can monitor heart cells with minimal disruption. Researchers from the University of Tokyo, Tokyo Women’s Medical University and Riken in Japan produced the device, which is a soft nanomesh sensor that comes in direct contact with the heart tissue.
The idea behind the sensor was conceived by Sunghoon Lee, a researcher at the University of Tokyo. Lee along with other collaborators supplied a healthy culture of cardiomyocytes derived from human stem cells. The researchers placed the nanomesh sensor on the top of the cell culture in a complex process, which involved removing and adding liquid medium at the proper times, to orient the device.
The sensors are made through a process called electro-spinning. When this happens, ultrafine polyurethane strands are extruded into a flat sheet, similar to how some common 3D printers work. Researchers then say this spiderweb like sheet is then coated in parylene, a type of plastic, to strengthen it. From there, 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. Researchers said that additional parylene isolates the probes, so their signals do not interfere with one another.
"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," Lee said in a release. "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."
Researchers said this sensor could help in the study of other organs and cells, as well as pave the way for future embedded devices.