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!
- - - - -

qPCR run w. strong positive NTC signal but very low fluorescence

  • Please log in to reply
1 reply to this topic

#1 Paja



  • Active Members
  • PipPipPipPipPip
  • 32 posts

Posted 13 September 2016 - 11:48 AM

Hi, I have a problem with positive non-template control (NTC). In some of my PCR systems I have the Cp of NTC only 1 cycle later than a regular sample! In some other systems the difference is 2 or 5 cycles. This is bad because it suggests massive contamination. Nevertheless, I have realized that dRn of the contaminated NTC samples is much much lower (10times or more) than the dRn of regular sample. I do not understand what is going on in this system, but I am convinced there may be a chance to work with it somehow in spite of that “contaminated NTC”, or even to somehow take advantage of this phenomenon (massively decreased fluorescence signal) in comparison with regular (positive) sample.  I would appreciate any suggestion. What does mean strong positive signal in NTC with very weak fluorescence?

Thank you! Paja

#2 bob1


    Thelymitra pulchella

  • Global Moderators
  • PipPipPipPipPipPipPipPipPipPip
  • 6,423 posts

Posted 13 September 2016 - 12:13 PM

Sounds like you have contamination. The dRN probably indicates that the banding is non-specific or diffuse if you ran it on a gel. However, contamination is contamination and you need to get rid of it before you can interpret your results.

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

©1999-2013 Protocol Online, All rights reserved.