CRISPR propels a smart hydrogel

The DNA hydrogel displays an enhanced response to target nucleic acid sequences Materials that respond to changes in temperature, light, electromagnetic field, or pH can have applications as controlled-release agents, responsive coatings, adaptive shape-memory materials, and sensing platforms (1). Response to more specific stimuli, such as pathogens, requires greater addressability and versatile control. DNA sequences can direct the responsiveness of materials with high specificity, and DNA, either incorporated into synthetic polymers or self-assembled to form responsive hydrogels (2, 3), can be used for biosensing, drug release, and therapy. In this regard, on page 780 of this issue, English et al. (4) report CRISPR (clustered regularly interspaced short palindromic repeats)–associated, nuclease-controlled DNA hydrogels, the functions of which can be tuned in response to user-defined target nucleic acid sequences. These stimuli-responsive materials could be used to perform controlled release of small cargoes, control electronic devices, and detect viruses with microfluidic devices.