DNA pelletinvisible vs visible
Posted 17 September 2012 - 10:24 AM
Anyone here that can tell me where I can find a good explenation on why clean/pure DNA pellets are invisible while the dirtier ones are the visible ones?
I know this is true, but cant find a good literature source for this.
I know its on wiki , but I am trying to find some good reasons, explenations for this or perhaps some paper on this.
Posted 17 September 2012 - 11:32 AM
wikipedia says: "White light reflected off objects can be seen when no part of the light spectrum is reflected significantly more than any other and the reflecting material has a degree of diffusion. People see this when transparent fibers, particles, or droplets are in a transparent matrix of a substantially different refractive index."
If you remember that the white pellet is a mixture of DNA and several different proteins (and other stuff such as salts, sugars...) and these have a different refractive index, because several types of proteins and salts are involved that surely influence how light passes through the pellet differently, this might be an explanation (don't forget that we perceive it as white, so it's a subjective perception and not more).
But perhaps someone else has a better explanation.
Edited by hobglobin, 17 September 2012 - 11:51 AM.
...except casandra's that belong to the funniest, most interesting and imaginative (or over-imaginative?) ones, I suppose.
Posted 24 November 2012 - 01:46 AM
I have not yet found a better explanation.