By modifying bacterial cellulose with magnetic nanoparticles, researchers from Stockholm University and the Royal Academy of Technology (KTH) have produced a hybrid nanocomposite that can be used as a magnetic hydrogel or an aerogel, and it can also be compressed to become a stiff nanopaper.

This new material could be used for a variety of purposes ranging from counterfeiting mechanisms for banknotes to high-gradient magnetic separation. Because nonoparticles can be controlled, it might also be conceivable that some very advanced printing applications might be developed in the future that would use this technology.

"The high porosity of the material (> 90 %) allows the flow of gases; whereas its hydrophilicity permits the absorption of aqueous solutions. Furthermore, thanks to the magnetic nanoparticles, the nanocomposite can be remotely actuated using a small magnet both in the dry and wet states," says Dr. German Salazar-Alvarez at Stockholm University's Department of Materials and Environmental Chemistry.

A major constituent of cotton or trees, cellulose is among the most abundant biopolymers on Earth. Cellulose is also present in algae and even some bacterial species can secrete a cellulose that is highly porous, strong, lightweight, and hydrophilic. Functionalization of nanocellulose offers a platform for production of low-cost, recyclable nanomaterials for both functional and structural applications.