1. how long can be ampicillin (dissovled in distilled water) stored at -20C and (in powder) at RT?
2. also, after dissolving the ampicillin powder into distilled water, the solution is passed through a 0.22uM filter. is it suitable to use a 0.22uM filter or we should use a 0.45uM filter?
3. is it necessary to use autoclaved distilled water or NANO water to dissolve the power? does this affect the results?
Thank you very much.
Edited by Samantha, 18 January 2005 - 10:02 PM.