快猫短视频

Wound repair is usually about fighting fire with fire 鈥� using sutures and staples that pull the skin together but that add more damage to the surrounding tissue in the process. But the job can be done without that additional damage using a silk and gold bandage sealed with a laser. What鈥檚 more, the approach may lower the risk of infection.

Kaushal Rege at Arizona State University and his colleagues developed a type of bandage that seals together wounds as effectively as sutures, but does not involve puncturing the skin. It is made of silk, which is dissolved and mixed with gold nanorods and then dried out into a thin strip.

When a laser is shone on the bandage, the gold converts the light into heat. The heat causes structural changes in the molecules of the silk and in the collagen of the tissue it鈥檚 applied to, and they intertwine like Velcro, bonding the silk to the tissue.

The researchers tested the silk sealant on bits of pig intestine filled with saline solution and found that the incisions closed up with lasers and the new bandage withstood seven times more fluid pressure before bursting than those closed with sutures. This makes bandage-patched wounds about as strong as the intact intestine. The new bandage also stopped bacteria from leaking between the inside and outside of the intestine.

They also tested the bandages on small incisions made in the skin of live mice. After two days of healing, the laser-sealed skin had less inflammation and was stronger than skin that was sutured or glued back together.

鈥淯nlike stitches, this provides a near-uniform coverage, which is important for better healing, and it can help minimise surgical site infections because you don鈥檛 have to pierce through the tissue,鈥� says Rege. The next step is to test it in larger animals with skin more similar to ours and make sure that the gold nanoparticles don鈥檛 cause any long-term side effects, he says.