Graphene magnetic beads
Graphene-doped magnetic beads for separation and purification (MaGO)
For separation and purification of basic dyes and aromatic molecules
Immagina MaGO beads have a magnetic core embedded in an agarose structure. Beads are doped with
Graphene Oxide or Reduced Graphene Oxide. MaGO are spherical beads with dimensions of about 50 µm.
The adsorption capacity of MaGO sample was tested using a set of aromatic positively charged dyes (Nile
Blue, Methylene Blue, Rhodamine 6G, and Crystal Violet). The results are reported in Figure 1. All the
molecules tested showed a high value of adsorption capacity and a very fast adsorption kinetics.
Nile Blu (NB, H2O)
Methylene Blu (MB)
Crystal Violet (CV)
Figure 1. Up: UV-visible spectroscopy of the NB, CV, MB, and Rh6G dyes solutions and the supernatants
after absorption for 1 minute with MaGO Table: Values of absorption capacity (Qt) and the absorption time of
the tested molecules.
TetramethylRhodamine molecules (TAMRA) and TAMRA-labelled antibody (IgG-TAMRA) incubated with
MaGO beads for 5-10 seconds followed by magnetic separation of the beads (Figure 2). As revealed from the
Uv-Vis absorption spectra and spectrofluorometric analysis, MaGO beads can efficiently remove the free dye
while the TAMRA-labelled antibody is still in solution (< 10% reduction).
Figure 2. A and B UV Vis of IgG-TAMRA and free TAMRA dye (black lines) incubated with MaGO beads
followed by vortexing for 5 seconds (red lines). C and D. Fluorescence emission of of IgG-TAMRA and free
TAMRA dye (black lines) incubated with MaGO beads followed by vortexing for 5 seconds (red lines).
Fast Protocol for free dye/protein separation
• Vortex the MaGO beads tube for 30 seconds
• Put the required MaGO beads volume in a new 1.5 mL tube
• Place the tube on the magnet to separate the beads. Remove the supernatant
• Resuspend the beads in your dye-protein mixture
• Vortex for 5-10 seconds
• Place immediately the tube on the magnet to separate the beads. Remove the supernatant enriched with
your labelled protein
• Discard the beads containing the free dye
Palladium decorated Graphene-doped magnetic beads for catalysis (MarGO-Xm)