Magneto-responsive hydrogels by self-assembly of low molecular weight peptides and crosslinking with iron oxide nanoparticles

Hydrogels that respond to non-invasive, external stimuli such as a magnetic field are of exceptional interest for the development of adaptive soft materials. To date magneto tuneable gels are predominantly based on macromolecular building blocks, while comparable low molecular weight systems are rarely found in the literature. Herein, we report a highly efficient peptide-based gelator (Nap GFYE), which can form hydrogels and incorporate Fe3O4 superparamagnetic nanoparticles in the gel matrix. The magnetic nanoparticles act as a physical crosslinker for the self-assembled peptide nanostructures and thus give rise to a fortified hybrid gel with distinctively improved mechanical properties. Furthermore, the particles provide the material with magnetic susceptibility and a gel to sol transition is observed upon application of a weak magnetic field. Magnetization of the inorganic-organic hybrid nanomaterial leads to on-demand release of an incorporated fluorescent dye into the supernatant.

Automated summary

The study reports a peptide-based gelator, Nap GFYE, that can form hydrogels and incorporate Fe3O4 superparamagnetic nanoparticles to create a hybrid gel that transitions from a gel to sol state upon application of a weak magnetic field. The magnetic nanoparticles act as crosslinkers for the self-assembled peptide nanostructures, enhancing the mechanical properties of the gel and enabling on-demand release of a fluorescent dye.