Drugs and cells can be delivered on demand by a porous material engineered to compress in response to an applied magnetic field.
David Mooney at Harvard University in Cambridge, Massachusetts, and his team prepared an alginate-based gel with micrometre-sized pores, and paramagnetic iron nanoparticles embedded throughout. On exposure to a magnetic field, the nanoparticles put the squeeze on the ferrogel. The authors used this to release a drug payload in in vitro experiments and, by implanting the gel into mice, for localized release of dye-stained stem cells.
With a reversible volume reduction of more than 70% (pictured), such ferrogels may also find applications as actuators and sensors in biomedical applications.
![](https://cdn.statically.io/img/media.springernature.com/w300/springer-static/image/art%3A10.1038%2F4681004c/MediaObjects/41586_2010_Article_BF4681004c_Figa_HTML.jpg)
Rights and permissions
About this article
Cite this article
Materials science: Magnetic gel delivers drugs. Nature 468, 1004 (2010). https://doi.org/10.1038/4681004c
Published:
Issue Date:
DOI: https://doi.org/10.1038/4681004c