A team of researchers at the Wyss Institute of Biologically Inspired Engineering at Harvard University has found a way to self-assemble complex structures out of gel “bricks” smaller than a grain of salt. The new method could help solve one of the major challenges in tissue engineering: creating injectable components that self-assemble into intricately structured, biocompatible scaffolds at an injury site to help regrow human tissues.
The key to self-assembly was developing the world’s first programmable glue. The glue is made of DNA, and it directs specific bricks of a water-filled gel to adhere only to each other, the scientists report in the Sept. 9 online issue of Nature Communications.
“By using DNA glue to guide gel bricks to self-assemble, we’re creating sophisticated programmable architecture,” said Peng Yin, a core faculty member at the Wyss Institute and senior co-author of the study. Yin is also an assistant professor of systems biology at Harvard Medical School (HMS). This novel self-assembly method worked for gel cubes as tiny as a piece of silt (30 microns diameter) to as large as a grain of sand (1 millimeter diameter), underscoring the method’s versatility.
The programmable DNA glue could also be used with other materials to create a variety of small, self-assembling devices, including lenses and reconfigurable microchips as well as surgical glue that could knit together only the desired tissues, said Ali Khademhosseini, an associate faculty member at the Wyss Institute who is the other senior co-author of the study.