Researchers at the University of California at San Diego have developed a small emerging sensor that can measure electronic signals that propagate inside heart cells. The technology consists of small spike-shaped protrusions that can penetrate cell membranes without causing damage and that can detect electrical signals within individual cells and between cells in 3D tissue samples. The device could provide new insights into heart disease, such as myocardial infarction and arrhythmias.
Cardiac tissue is intrinsically dependent on electrical activity for proper functioning, and measuring it accurately at the cellular and intercellular level could provide a wealth of information on the basis of numerous heart diseases. However, the insertion of tiny electrodes into individual cells is difficult and can cause damage. This newer technology aims to provide a less invasive way to achieve this.
“Studying how an electrical signal propagates between different cells is important for understanding the mechanism of cell function and disease,” said Yue Gu, one of the scientists who led the development of the new sensor. “Irregularities in this signal can be a sign of arrhythmia, for example. If the signal cannot be properly propagated from one part of the heart to another, then some part of the heart cannot receive the signal, so it can be contracted “.
The basis of the device is a series of small field effect transistors that researchers have coated with a bilayer of phospholipids. This coating allows them to penetrate inside the cell without causing a foreign body response, making it difficult to measure long-term electrical activity. Tiny probes are sensitive enough to measure electrical signals within a cell, but they can also track signals traveling through multiple cells.
The device features a “pop-up” structure, as the researchers attached the transistors to a pre-stretched elastomer sheet, and when they released the voltage, the transistors were erected to form a 3D structure. “It’s like an emerging book,” Gu said. “It starts as a 2D structure and, with compressive force, appears in some parts and becomes a 3D structure.”
So far, the UCSD team has tested the technology in cardiac cell cultures in the laboratory and has already gotten some ideas about the speed at which signals propagate through individual cells and groups of cells. · Cells. However, the device may also have the potential to investigate neurological diseases and could allow researchers to study electrical impulses within neurons.
Study a Nature Nanotechnology: Three-dimensional transistor arrays for intra- and intercellular recording