Octopus power: Engineers create squid-like sucker to move delicate tissue grafts during surgery

CHAMPAIGN, Ill. — Surgery can be a very delicate process. For surgeons, moving tiny and fragile grafts or electronics into the human body can be even trickier. Researchers from the University of Illinois at Chicago have created a new tool which can save these transplants. Unlike breakthroughs that turn to robots however, this invention is turning to an unusual source — the octopus.

“For the last few decades, cell or tissue sheets have been increasingly used to treat injured or diseased tissues. A crucial aspect of tissue transplantation surgery, such as corneal tissue transplantation surgery, is surgical gripping and safe transplantation of soft tissues. However, handling these living substances remains a grand challenge because they are fragile and easily crumple when picking them up from the culture media,” explains study leader and professor of chemical and biomolecular engineering Hyunjoon Kong in a university release.

Instead of trying to pick up a cell graft with tweezers or other instruments, the Illinois team was inspired by the sucker of an octopus or squid. These creatures are able to pick up wet and dry objects just by making small pressure changes in their muscle-powered suction cups. This allows them to grip objects of all shapes without the need for sticky chemical substances or punctures.

Making surgery easier

Currently, physicians have to first grow these tissue or cell sheets in temperature-sensitive, soft polymer dishes. Once they are transferred, these sheets shrink and release a thin film. Transferring these grafts is the problem. Researchers say the process takes between 30 and 60 minutes and relies on technicians not wrinkling or tearing the sheet throughout the entire transplant.

“During surgery, surgeons must minimize the risk of damage to soft tissues and transplant quickly, without contamination. Also, transfer of ultrathin materials without wrinkle or damage is another crucial aspect,” Kong says.

The new octopus-like manipulator utilizes a layer of temperature-responsive hydrogel attached to an electric heater. To mimic the suction action of an octopus, the hydrogel layer is heated which causes it to shrink. Researchers then press the manipulator to the graft and turn off the heat. This causes the hydrogel to expand and the pressure change creates the suction effect, grabbing the tissue or electronic device.

From there, the graft is moved to the patient and placed in the right spot. Turning the heat back on releases the sheet from the suction grip, without rips or tears. According to the study, the new process takes just 10 seconds.

Researchers are now hoping to add sensors to their squid-like device. This will help scientists monitor the shape and stability of the graft the device is picking up. Kong’s team worked with researchers from Purdue University, Chung-Ang University in South Korea, and the Korea Advanced Institute for Science and Technology. Their study appears in the journal Science Advances.