Purdue Researchers Develop Fast-Synthesizing, Photodegradable Hydrogels for Next-Generation Biomaterials

Chien-Chi Lin is a Professor of Biomedical Engineering in the Weldon School of Biomedical Engineering, Indianapolis
A Purdue Biomedical Engineering team has unveiled a major advance in hydrogel design—creating a new class of photodegradable biomaterials that can be rapidly synthesized and precisely controlled with light. The work, led by PhD student Nathan Dimmitt, graduate researcher Jonathan Bryan and Professor Chien-Chi Lin, introduces a faster, cleaner way to produce norbornene-functionalized hydrogels and opens the door to new capabilities in tissue engineering, drug delivery and biofabrication.

Thiol-norbornene hydrogels are widely used because they form predictable, uniform cross-linked networks ideal for studying cell behavior or building soft tissue scaffolds. But the field has long relied on traditional PEG-norbornene (PEGNB) macromers—materials that require long reaction times and a malodorous starting reagent. Purdue’s team developed a new variant, PEG-amide-norbornene-carboxylate (PEGaNBCA), that solves both problems.

Using a microwave reactor, the researchers reduced the synthesis time from 48 hours to just over 20 minutes, while boosting the degree of norbornene substitution to more than 93%. The simplified, aqueous reaction not only improves efficiency—it makes the material more practical for widespread use.

The team also made a surprising discovery: when photo-cross-linked, PEGaNBCA hydrogels form thioether bonds that are hydrolytically stable yet susceptible to light-driven, radical-mediated degradation. By adjusting light intensity, wavelength and photoinitiator levels, the researchers demonstrated finely tunable photodegradation, giving users temporal and spatial control over when and where the hydrogel breaks down.

The Lin Research Group disclosed their innovative technologies to the Purdue Innovates Office of Technology Commercialization, which has applied for patents to protect the intellectual property.