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By labcat on Tuesday, August 10, 2004 - 04:40 am:
We currently use a 0.01% sodium azide soln as a preservative for a Human Serum Albumin HPLC chiral colum, preparing the soln freshly each time we need it.
I would appreciate it very much if anybody could suggest me a storage time for this soln, to be able to write an expiry date in a SOP.
Incidentally, this is also a question about the efficacy of the preservative: may I leave the column (in a fridge) for three months, or shall I change the sodium azide after a shorter period?
Thank you all for any suggestion
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By Chris Pohl on Saturday, August 21, 2004 - 05:41 pm:
Labcat,
I can't give you any specific lifetime data on such a solution but I do know that sodium azide solutions are not very stable. They degrade fairly rapidly to sodium nitrate, especially at lower concentrations. You can easily determine the degradation rate of your solution using ion chromatography. In my experience, concentrations in the range you specify need to be made up frequently enough that I'd generally prepare a fresh standard rather than working from an old stock solution. I doubt the solution will last a month at room temperature.
We currently use a 0.01% sodium azide soln as a preservative for a Human Serum Albumin HPLC chiral colum, preparing the soln freshly each time we need it.
I would appreciate it very much if anybody could suggest me a storage time for this soln, to be able to write an expiry date in a SOP.
Incidentally, this is also a question about the efficacy of the preservative: may I leave the column (in a fridge) for three months, or shall I change the sodium azide after a shorter period?
Thank you all for any suggestion
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By Chris Pohl on Saturday, August 21, 2004 - 05:41 pm:
Labcat,
I can't give you any specific lifetime data on such a solution but I do know that sodium azide solutions are not very stable. They degrade fairly rapidly to sodium nitrate, especially at lower concentrations. You can easily determine the degradation rate of your solution using ion chromatography. In my experience, concentrations in the range you specify need to be made up frequently enough that I'd generally prepare a fresh standard rather than working from an old stock solution. I doubt the solution will last a month at room temperature.
