Jump to content

  • Log in with Facebook Log in with Twitter Log in with Windows Live Log In with Google      Sign In   
  • Create Account

Submit your paper to J Biol Methods today!
Photo
- - - - -

DNA pellet

invisible vs visible

  • Please log in to reply
2 replies to this topic

#1 lyok

lyok

    Veteran

  • Active Members
  • PipPipPipPipPipPipPipPipPipPip
  • 201 posts
6
Neutral

Posted 17 September 2012 - 10:24 AM

D ear all,

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.

thanks

#2 hobglobin

hobglobin

    Growing old is mandatory, growing up is optional...

  • Global Moderators
  • PipPipPipPipPipPipPipPipPipPip
  • 5,508 posts
94
Excellent

Posted 17 September 2012 - 11:32 AM

Well a good question, and actually I have no real idea (and physics exams are long ago Posted Image )..
Anyway:
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.

One must presume that long and short arguments contribute to the same end. - Epicurus
...except casandra's that belong to the funniest, most interesting and imaginative (or over-imaginative?) ones, I suppose.

#3 lyok

lyok

    Veteran

  • Active Members
  • PipPipPipPipPipPipPipPipPipPip
  • 201 posts
6
Neutral

Posted 24 November 2012 - 01:46 AM

Ok thanks.
I have not yet found a better explanation.




Home - About - Terms of Service - Privacy - Contact Us

©1999-2013 Protocol Online, All rights reserved.