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
- - - - -

question about media color


  • Please log in to reply
4 replies to this topic

#1 soymilk14

soymilk14

    Enthusiast

  • Active Members
  • PipPipPipPipPip
  • 81 posts
1
Neutral

Posted 29 December 2009 - 10:57 PM

hello everyone,

i just want to ask about the possible reasons for different changes of culture media. I prepared RPMI with different serum (FBS) and added antibiotic, glutamine, and 2-mercaptoethanol. I am expecting that the color of the media will be the same for all bottles even with different manufacturer of serum, but I just want to know reasons why some are pinkish, light pink, and others are so red. does the change in color also mean change in pH and contamination?

thank you....

#2 Carlton H

Carlton H

    Enthusiast

  • Active Members
  • PipPipPipPipPip
  • 95 posts
0
Neutral

Posted 30 December 2009 - 02:24 PM

I'm not sure this is the reason, but it could potentially be photobleaching.
NextAdvance
Reliable laboratory instruments for the life sciences, designed to enable you to work more effectively and increase productivity. Check us out!

If my answers help you, please take a moment to check out our site and see if any of our products would help you as well! Thanks!

#3 sanjiun

sanjiun

    Enthusiast

  • Active Members
  • PipPipPipPipPip
  • 39 posts
0
Neutral

Posted 30 December 2009 - 06:11 PM

After sometime after open the bottle/ prepared the media, the media wil change its colour. It is not contamination. Maybe some oxidization, i guess.

#4 miBunny

miBunny

    Veteran

  • Active Members
  • PipPipPipPipPipPipPipPipPipPip
  • 130 posts
1
Neutral

Posted 30 December 2009 - 07:16 PM

The color of the media is due to the presence of phenol red. Phenol red is included in media as a pH indicator. Each bottle may have been exposed to air for different amounts of time as you prepared your media or the FBS may have a different pH (I have never heard this before but maybe it is possible).

#5 klinmed

klinmed

    Veteran

  • Active Members
  • PipPipPipPipPipPipPipPipPipPip
  • 209 posts
2
Neutral

Posted 31 December 2009 - 04:22 AM

hello everyone,

i just want to ask about the possible reasons for different changes of culture media. I prepared RPMI with different serum (FBS) and added antibiotic, glutamine, and 2-mercaptoethanol. I am expecting that the color of the media will be the same for all bottles even with different manufacturer of serum, but I just want to know reasons why some are pinkish, light pink, and others are so red. does the change in color also mean change in pH and contamination?

thank you....

Most cell culture media are buffered using a carbonate/bicarbonate buffer system (the bicarbonate in the media also supplies a metabolic requirement). When the media is exposed to air it slowly loses C02 and becomes more alkaline (and the phenol red pH indicator becomes more red). This is why cultures need to be incubated in 5% CO2 to maintain pH.
The variations in the colors of your media are due to the different times the individual bottles were open during the addition of supplements (hence diff losses in the amount of CO2). Also some bottles may not be sealed as well as others.
If you place the different media into a 5% CO2 atmosphere for a few hours they will all take on the same color.

To minimize pH changes during cell handling people often include 10-20 mM HEPES buffer (pH 7.2) in their medium.

Hope this helps.




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

©1999-2013 Protocol Online, All rights reserved.