I'm using RPMI 1640 media from Himedia. Within 24 hours the colour of the media is changing to yellow even with very low density of cells. I have checked for any kind of contamination, but that is not the case. Cells also seem to be fine. I read in the datasheet that RPMI should not be stored in presence of bright light. We store it in a fridge with white light. Is there any component in it which photosensitive and degradable? What else can cause the frequent colour change?
The light sensitivity is usually the vitamins in the medium. With the fridge door closed the light should hopefully be off.
Have you confirmed that the CO2 is balanced in your incubator and that you aren't much higher than 5%?
Dear Yaron,
Thanks for your answer.
1.No, Our's is a cell frost fridge which has a continuous white light, so is that much light exposure harmful for the media components?
2. The CO2 is balanced in the incubator as I use DMEM also for other cell lines and the colour change for it is fine.
Is there any other reason which can trigger change in pH and subsequently the change in media colour?
I believe your RPMI 1640 medium from Himedia contains Hepes. Hepes will help maintaining physiological pH in cell culture. It is also light sensitive. It is therefore strongly advised to keep HEPES-containing solutions in darkness as much as possible.
Not all RPMI-1640 formulations contain HEPES, only specifically modified formulations.
Generally, I would recommend you keep your medium in the dark so wrap it in aluminum foil if you can.
What happens if you keep it in the incubator with no cells at all?
Hi saha,I think this problem for PH your medium,what PH media?also I recommend you keep your medium in the dark.
There must be some issue of pH in your media. I am using this media from himedia. I never come across such type of problems.
Can u tell me The brand of your RPMI and Serum, and also cells you're seeding... If they are cancerous it is an obvious reason for media being exhausted.
Dear Singh,
As I mentioned RPMI is from Himedia and Serum from thermofisher. The colour change was too early even for cancerous cells. But I think, I stored it in light and as others suggested the photosensitive buffer compenent HEPES must have gone bad and lead to the quicker pH change.
We store our media in light all The time... Did u noticed any color change when u add in The Serum.. Actually once we recieved a media from himedia which would change color to orangish soon after we add in Serum. And that does not mean The media is exhausted. As long as your cells are not stressed and proliferate fine... This shouldnt be an issue
It was with just that batch. We started using media from sigma after that
Hi Tias Saha
I have exactly the same problem with RPMI media from Sigma.....
please if you can help me by telling me what happened with you after that?? is the color changing was related to any problem?.
for me it is like what you mentioned previously, the cells look OK and there is no evidence of contamination... but maybe only slower growth!!.... have you faced this??
- Badges
- Science method