Lasers and Glue May Help Weld Tissue Ruptures, Beneficial for Colorectal Cancer and IBD

A new study suggests that lasers could help weld intestines together with the aid glue that's filled with microscopic gold rods.

This would be a great benefit for such health issues as colorectal cancer and inflammatory bowel disease, both of which afflict about 1.5 million people in the United States annually. When performed correctly, the surgery to remove diseased tissue from intestinal holes are common and can help prevent life-threatening bacterial infections.

Lasers are already able to weld ruptures in tissues such as cartilage, blood vessels, corneas, livers, urinary tracts, nerves and skin together by causing proteins to fuse. This stitch-free way of sealing holes is especially helpful in places where sutures and staples may not work, such as thin, fragile tissues.

However, researchers note that conventional laser tissue welds may be weak. To solve this problem, chemical engineer Kaushal Rege at Arizona State University in Tempe and his colleagues are developing a protein-based glue that can act as a solder that lasers can heat to patch up holes.

When heated, the goo solidifies into an elastic material that can behave "much like a rubber band," Rege said. "Tissues like colons have to transport matter through them, and the elasticity of materials patching up holes is important."

Researchers indicate that the material is composed primarily of artificial proteins, but embedded within it are tiny gold rods that are only 15 nanometers-or billionths of a meter-wide and 50 nanometers long.

The nano-rods absorb near-infrared light, which passes harmlessly through human tissue for the most part, causing them to heat up enough to coagulate the surrounding proteins in the goo.

The researchers successfully used laser welding and their goo to patch holes up to several millimeters large in pig guts. These welds significantly increased the amount of pressure needed to cause leakage or bursting of repaired tissues and created liquid-tight seals that prevented gut bacteria from sneaking out.

Researchers note that they are hoping to follow experiments later with live animals.