Purification of Complex Liquids

Wastewater purification

Carbon coated magnetic metallic nanoparticles are well suited to treat industrial wastewater. Their carbon coating gives them a high stability under a wide range of different conditions (pH, temperature) and allows the covalent binding of highly specific chelating agents. In our laboratory, we use these newly produced magnetic chelators to purify water from a targeted atoms or molecules. The extremely highly magnetic saturation of these magnetic chelators enhances the efficiency of their collection in a high gradient magnetic filter and thus permits the treatment of large volumes in a short period of time. The magnetic chelators have already proven their ability to remove specifically heavy metal or noble metal in a lab scale pilot plan. We are currently building a continuous magnetic wastewater treatment set-up to further optimize this separation method.

Blood purification

We investigate the direct injection of stable carbon coated metal nanomagnets into whole blood for the efficient, magnetic extraction-based extracorporeal removal of low and high molecular compounds. We demonstrated the successful extraction of metal ions (Pb²⁺), steroid drugs (digoxin, cardiac drug) and proteins (interleukin-6 (IL-6), inflammatory mediator) whilst monitoring blood integrity using a series of clinically important parameters. Combined with existing therapies, these results may have major implications for the treatment of severe intoxications (digoxin, barbiturates), sepsis (specific filtering of (multiple) cytokines or toxins), metabolic disorders (thyreotoxicosis, hyperfibrinogenemia and hyperlipoproteinemia) and auto-immune diseases (removal of pathogenic auto-antibodies or immune-complexes).

We are currently developing an extracorporeal blood purification device to exploit the efficiency of nanoparticle-based blood purification in an ex vivo setup.


Further reading:

• I.K. Herrmann, R.E. Bernabei, M. Urner, R.N. Grass, B. Beck-Schimmer and W.J. Stark, Device for Continuous Extracorporeal Blood Purification using Target-specific Metal Nanomagnets, Nephrol. Dial. Transplant. (2011).
  DOI: 10.1093/ndt/gfq846
• I.K. Herrmann, M. Urner, F.M. Koehler, M. Hasler, B. Roth-Z'Graggen, R.N. Grass, U. Ziegler, B. Beck-Schimmer, W.J. Stark, Blood Purification Using Functionalized Core/Shell Nanomagnets, Small, 6(13), 1388-92 (2010).
  DOI: 10.1002/smll.201000438
• I.K. Herrmann, R.N. Grass, W.J. Stark, High-strength metal nanomagnets for diagnostics and medicine: carbon shells allow long-term stability and reliable linker chemistry, Nanomedicine, 4(7), 787-98 (2009).
  DOI: 10.2217/nnm.09.55
  
• M. Rossier, F.M. Koehler, E.K. Athanassiou, R.N. Grass, B. Aeschlimann, D. Günther, W.J. Stark, Gold adsorption on the carbon surface of C/Co nanoparticles allows magnetic extraction from extremely diluted aqueous solutions, J. Mater. Chem., 19, 8239-43 (2009).
  DOI: 10.1039/b913744k
  
• F.M. Koehler, M. Rossier, M. Waelle, E.K. Athanassiou, L.K. Limbach, R.N. Grass, D. Günther, W.J. Stark, Magnetic EDTA: coupling heavy metal chelators to metal nanomagnets for rapid removal of cadmium, lead and copper from contaminated water, Chem. Commun., 32, 4862-4 (2009).
  DOI: 10.1039/b909447d