Impurities in PBS - any suggestions (May/27/2008 )

Hi
I used to autoclave the PBS at 121c for 20 minutes,Now Iam using Merk PBS I found impurities and bulks after autoclaving. any suggestions
Thanks

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If the impurities appeared immediately after autoclaving, then they are most likely insoluble. For this, I would run it through a 0.22micrometer filter unit.
If the impurities appear after the PBS has cooled, try heating it up on a hot plate. If the impurities do not dissolve, run it through a filter unit.

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Are the impurities not appearing before autoclaving?? Just check for that......
if the impurities are appearing only after autoclaving then its better to go for membrane sterilization.

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I would definitely call/mail Merk tech. If you have not mixed it up, you may get money back and save a lot of other people from this trouble.

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Is there Mg in it? This can precipitate after autoclaving...there was a thread about this some weeks ago

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Thanks for all ur suggestions,the impurities appeared after autoclaving I think I'd better email merk

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That was me, actually. The end of the story is that I found Dulbecco's PBS is exactly the same formula (PBS w/Mg, Ca), and only costs about $21 for 6 500mL bottles. It's not worth our trouble to autoclave or sterile filter when we can buy it that cheap.

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thank you! I could not remember who asked the question, but kept the pecipitation thing in mind, just in case of
Good for you that you could find such a cheap soulution....

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