Light-Triggered Bioactivity in Three Dimensions


  • This work was supported by the National Science Foundation under grant DMR-0505772 and by the Department of Energy under grant DE-FG02-00ER45810. T.M. thanks the JSPS for his Research Fellowship for Young Scientists. We thank L. Palmer for a fruitful discussion. We thank M. Greenfield for help with the rheometer and the following Northwestern University facilities for use of their instruments: BIF, EPIC, IMSERC, Keck, and MRC.


original image

Photocleavage of a 2-nitrobenzyl group in a bioactive peptide amphiphile containing the Arg-Gly-Asp (RGD) epitope triggers a sol-to-gel transition as nanospheres are converted to nanofibers (see picture). This morphological change enhances the bioactivity of the nanostructures surrounding cells in three dimensions.