Scientific article: Mopping heavy metals with nanoparticles

Three research groups combined their expertise to develop magnetic core-shell nanoparticles that would be colloidally stable, efficiently bind heavy metal ions and have a core that could allow magnetic extraction to remove the captured toxic ions. With a theoretical model describing the particles, this proof-of-concept published in ACS Applied Materials & Interfaces can now be further explored and optimized for applications.

Through the ERASMUS exchange program, Ph.D. student Elia Roma from the research groups of Tecla Gasperi and Barbara Capone in Rome, could join BIMat to explore our leading platform for synthesizing polymer-grafted, superparamagnetic nanoparticles. By building on previous work, we designed a block copolymer, where one part is thermoresponsive and allows control over the colloidal stability. The other part was a polymer which should display affinity to heavy metal ions that are toxic to the environment.

These polymers were grafted to superparamagnetic nanoparticle cores, to produce easily dispersable nanoparticles, which maximizes the possibility to encounter and remove ion. The thermoresponsive shells make it possible to thermally aggregate the particles and extract them with a magnet.

The proposed function of the nanoparticles was tested using isothermal titration calorimetry for the heavy metal binding and dynamic light scattering for the colloidal behavior.

Our colleagues in Rome modeled the expected behavior of the mopping ability of the nanoparticles and found a good agreement with the experimental results.

This combination of results is leading us to refined designs that could lead to real-world applications.

Our results are published in ACS Applied Materials & Interfaces as “Theoretical and Experimental Design of Heavy Metal-Mopping Magnetic Nanoparticles”.