Combining bee spit and flower oil could usher in new era of super glues

28 Mar 2019

Image: © azur13/Stock.adobe.com

Researchers have turned to the power of bee spit to begin the process of creating glues of unique stickiness.

Have you ever wondered how bees are able to transport large amounts of pollen back to the hive without dropping any, even in the middle of a sudden rainstorm? The answer can be found in the combination of ‘bee spit’ and flower oil that they use to keep their cargo firmly in place.

Now, researchers at Georgia Tech have looked into the super adhesive to find a way to allow us to create a whole new range of glues that could remain sticky, whatever the weather.

In a paper published to Nature Communications, the research team was able to describe how the two natural liquids work together to protect the bee’s bounty during travelling.

The first component of the bioglue is the bee’s own salivary secretions, which coat the pollen grains, forcing them to stick together. This sugary secretion is the main ingredient of honey and is produced from the nectar they drink from flowers.

The second ingredient is a plant-based oil called pollenkitt, which coats the pollen grains and helps stabilise the adhesive properties of the nectar to protect it from the impact of too much or too little humidity.

“It works similarly to a layer of cooking oil covering a pool of syrup,” said researcher Carson Meredith. “The oil separates the syrup from the air and slows down drying considerably.”

Creating a buzz

To test the adhesive properties in the lab, the team separated the oil from the bee spit and looked at how sticky the nectar remained under various humidity conditions. As expected, its stickiness diminished as the nectar began to absorb more water, as well as when humidity was decreased as it dried out.

“We believe you could take the essential concepts of this material and develop a novel adhesive with a water-barrier external oil layer that could better resist humidity changes in the same way,” Meredith said. “Or, potentially, this concept would apply to controlling the working time of an adhesive, such as its ability to flow and time to dry or cure.”

But one question remained: how do the bees remove the pollen when they return to the hive? The research team believes that it may be down to the adhesive’s rate-sensitive response. In other words, the faster the force attempting to remove it, the more it would resist.

“This is a property of capillary adhesion, which we believe could be harnessed and tailored for specific applications, such as controlling motion in microscopic or nanoscale devices, in fields ranging from construction to medicine,” Meredith said.

Colm Gorey was a senior journalist with Silicon Republic

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