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shelf life of "fluid" 7H9

| posted 05 Aug, 2016 15:29
As I guess many/most of us do, we make top agar in two components: a 2XL agar and what we refer to as a "fluid" portion which is just 7H9. We have a fair bit left over from last fall that was probably made back in late October. Does anyone have a handle on the shelf life of this stuff at room temperature? I'd hate to throw it out if it's still perfectly good, but it concerns me because I think it contains a fair number of low molecular weight organic compounds that may not do well in solution over time.
| posted 06 Aug, 2016 12:11
HI! If you haven't lost volume (water), I think you are OK. If you have dropped the volume significantly, you might want to add some sterile water. I don't think you will have trouble with the degradation of small molecules. Just include its date in your lab notebook, so if a pattern presents itself, you will be able to link it to this component.
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