A biological glue made from mistletoe

A naturally sticky material produced by mistletoe plants could have medical uses

Spotted: In many parts of the world, mistletoe is associated with kisses and Christmas. But now, researchers at McGill University and the Max Planck Institute of Colloids and Interfaces have published research into the potential medical use of a mistletoe product – a gluey thread called viscin.

Viscin is a sticky mucilaginous tissue produced by mistletoe that helps the parasitic plant stick to its host. The material further helps to disperse mistletoe seeds by sticking them to passing birds. The inspiration for the study came from lead researcher Matthew Harrington, who noticed his daughter playing with mistletoe berries and was struck by how they stuck to anything and everything.

The researchers were able to determine that, with minimal processing, viscin fibres could be stretched into thin films or assembled into 3D structures that stick to both themselves and other materials. This includes several synthetic surfaces, such as plastics, glass, and metal alloys – along with skin. Even more intriguing, this ‘stickiness’ is reversible under very humid conditions. These properties raise the possibility that viscin could be used for a range of medical applications, such as sealing wounds.

Nils Horbelt, a recently graduated PhD student at the Max Planck Institute and first author on the paper, describes his experiments with viscin’s reversible stickiness. “I wore a thin film of viscin on my skin for three days to observe its adhesive qualities and was able to remove it from my fingers afterwards by simply rubbing them together,” he said.

The search for useful and sustainable bio-materials is accelerating all the time. Some recent innovations in this area include edible food packaging made from kelp and a sound absorber made from fungus. This research is an example of how bio-materials can also have medical uses.