Syracuse Sun

Professor Xiaoran Hu from the College of Arts and Sciences has made strides in developing molecules that undergo mechanochemical transformations. These molecules, called mechanophores, could be crucial in assessing nanoscale stress in synthetic plastics and biomaterials, aiding in studying mechanobiology processes.

Plastic components are prevalent in infrastructure and transportation, making their durability a concern. "When mechanical forces cause stress and deformation that go unnoticed in the plastic engineered parts of an airplane, for instance, it can cause significant consequences that we want to avoid," said Xiaoran Hu, who is also a member of the BioInspired Institute. Supported by the University and the ACS Petroleum Research Fund, Hu's research aims to mitigate risks and expenses associated with maintaining plastic components by using mechanophores that change characteristics, like color, in response to mechanical stress.

The team, based in Syracuse, has developed "configurational mechanophores" that undergo isomerization reactions upon activation, offering a visual signal of mechanical events. This sensitivity makes their method unique. As stated in a Journal of the ACS study, the chemical transformation of Hu's mechanophores can be triggered by mechanical forces as low as 131 piconewtons, much less than the forces required for other known mechanochemical reactions. For comparison, reactions involving carbon-carbon bond scission need forces on the nanonewton scale, or about 1,000 times stronger than what Hu’s sensors can detect.

Moreover, these mechanophores are more stable against heat and light, broadening their application range. Their high sensitivity could also benefit biological studies, possibly revealing stress changes at the molecular level that were previously hidden.

The research not only focuses on the current developments. Hu indicates future goals of creating "next-generation molecular force sensors with further enhanced mechanosensitivity," which might lead to smarter plastics and more insights into cellular processes. "We also aim to apply our mechanophores to different materials platforms such as mechanosensitive elastomers and paints to develop safer and smarter plastics," Hu shared.