A compound that could turn an entire swimming pool into jelly

Though it sounds suspiciously like Kurt Vonnegut's ice-nine from Cat's Cradle, a materials chemist at Radboud University Nijmegen in the Netherlands has concocted a polymer that could turn an entire swimming pool into jelly. All that would be required is ample amounts of the compound, some warmth, and 25 minutes of time. The substance, called polyisocyanide polymer, is the first synthetic polymer that can equal the strength and rigidity found in many biological compounds, including living cells.

As Mark Peplow reports in Nature News, Radboud hasn't actually tried this experiment, but he's pretty sure it would work. But more importantly, he's excited about the materials breakthrough and what it could mean to the biomedical field.

Indeed, 'mechanical responsiveness' is a characteristic essential to the integrity of all biological systems, from tissues right down to cells. A sufficiently durable and robust material — one that could be generated on demand with a handy compound — could pave the way for advancements in drug delivery and tissue engineering.

For example, a cold solution of the polymer could be poured onto a wound to protect the tissue by quickly forming a gel barrier (i.e. a hydrogel) after it warms to body temperature.

Peplow explains how polyisocyanide polymer works:

A compound that could turn an entire swimming pool into jelly

Rowan's polymer strands have a helical backbone with thousands of short peptides jutting out from the sides, each carrying long tails made of repeating carbon and oxygen chains. Nitrogen and hydrogen atoms in neighbouring peptides bond to each other to give the backbone rigidity, and the carbon and oxygen tails readily grab water molecules, making the polymer extremely soluble.

Once the polymer is dissolved, warming it causes the tails to squeeze water molecules away and form links with neighbouring polymer strands. Above a certain temperature, the solution transforms into a gel in seconds as the strands self-assemble into bundles roughly 10 nanometres wide. As with the biopolymers in a living cell, or the fibres in a rope, the bundling stiffens the whole structure. "The nanoscale mechanism is the same as at the macroscale," says Rowan.

Researchers already knew that bundling was important in strengthening biopolymers. But Rowan's team has measured the stiffness of individual strands and of the bundles, and has shown the relationship between the two. "Now that we understand the principles, we can start making gels at even lower concentrations," predicts Rowan.

The entire study can be found here.