Researchers from MIT and the Swiss Ecole Polytechnique de Lausanne have discovered how it is that gold nano particles penetrate cell walls without destroying the cell.
After numerous lab experiments in combination with computer simultations, the researchers concluded that the first key is the nanoparticle fusion with lipids in the cell wall. The second is that the cell wall membrane, after the gold nanoparticles have made their way in, immediately seals the membrane, preventing any other small molecules from leaking in.
Scientists suggest that because the nanoparticles are completely coated with a monolayer of "hydrophobic and hydrophilic components…the fact that they are made of gold doesn't have any direct effect, except that gold nanoparticles are an easily prepared model system."
But gold particles are said to have "therapeutic properties," and, more importantly, they capture X-rays well,"so if they could be made to penetrate cancer cells, and were then heated by a beam of X-rays, they could destroy those cells from within."
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