What is happening when we coat either Au or W particles?
Adsorption
Adsorption is where a layer of molecules cling to a surface.
1.
There is the adsorbate (i.e. DNA plasmid)
2.
There is the adsorbent (i.e. W)
What attracts the adsorbate and the adsorbent to each other so that they are held together in Adsorption?
DNA has a – charge. W
has + charge. Under the right
conditions, a bond is formed. If the DNA is in solution with the W and the
bond forms, the DNA will precipitate and adsorption occurs. The DNA is not present in the solution
anymore, it is now coating the W microparticle.
That’s very beautiful and simple to understand but as may be
expected the devil’s in the details.
