New York, Feb 5 (IANS): Researchers have developed a flexible, microscopic hand-like gripper for robots that could help doctors perform remotely guided surgical procedures or conduct biopsies.

This added trait could help in the micro assembly or microengineering of soft or biological parts, or give surgeons the ability to remotely direct where biopsies are taken, the researchers noted.

The materials also could someday deliver therapeutic drugs to hard-to-reach places, said David Gracias from the Johns Hopkins University.

Many robotic tools require cords to provide power to generate their movements. But cords add to the bulk of robots, which limits the spaces they can access, Gracias pointed out.

To address this constraint, the scientists turned to hydrogels.

These soft materials can swell in response to changes in temperature, acidity or light, providing energy to carry out tasks without being tethered to a power source.

However, hydrogels are too floppy for some applications, so the group combined the hydrogels with a stiff biodegradable polymer, making the microhands strong enough to wrap around and remove cells.

The researchers then incorporated magnetic nanoparticles in the materials so they could guide the microhands with a magnetic probe.

The use of soft materials also highlights the possibility of creating biodegradable, miniaturised surgical tools that can safely dissolve in the body, Gracias added.

The study appeared in the journal ACS Applied Materials & Interfaces.