A nano ’stealth’ probe created to eavesdrop on cells

WASHINGTON - Researchers have created a nano-sized probe that can be slipped stealthily into a cell wall and help it ‘eavesdrop’ on cellular activity.

Everything from signals generated as cells communicate with one another to “digestive rumblings” as they react to medication could be monitored for up to a week, say Stanford engineers.

Current methods of probing a cell are so destructive they usually only allow a few hours of observation before the cell dies. The first ever nano stealth probe can be planted into a cell wall without damaging it.

The key design feature of the probe is that it mimics natural gateways in the cell membrane, said Nick Melosh, assistant professor of materials science and engineering at Stanford University, in whose lab the research was done.

With modification, the probe might serve as a conduit for inserting medication into a cell’s heavily defended interior, he said.

It might also provide an improved method of attaching neural prosthetics, such as artificial arms that are controlled by pectoral muscles, or deep brain implants used for treating depression.

In the lab, the 600-nanometre-long, metal-coated silicon probe integrates so smoothly into cell membranes that researchers have named it the “stealth” probe. A nanometre is a billionth of a metre, said a Stanford release.

“The probes fuse into the membranes spontaneously and form good, strong junctions there,” Melosh said. The attachment is so strong, he said, “We cannot pull them out. The membrane will just keep deforming rather than let go of the probes.”

Melosh co-authored the paper with Benjamin Almquist, a Stanford graduate student in materials science and engineering.

These findings were published in the Proceedings of the National Academy of Sciences.