Shelf life of self prepared solvents - Discussion about shelf life of self prepared solvents (Jun/05/2010 )
Hi!
I'm looking for som literature or something valid information about the shelf life of self prepared solvents. Generally if I make an 1 M NaOH solution, I shall give to exiry date 1 month after producing date? And in case of 1% CMC solutions (using as vehicle in toxicology research) shall I follow this 1 month as a main guide line? Unfortunatelly I'm new in this topic, and I don't have enough information about this. Can somebofy help me? THX!
Quality systems often demands a expiry date but I find it hard to do so because to be sure it's valid you have to test it for a long period and big number of solutions at every test it's used in.
If you pick a date of wich you want to be certain it's ok then you will have to dispose a lot of perfect working solutions and make a lot of not nessecary costs.
Take for instance the NaOH 1M solution and it's used for correcting a buffer used in a test that is not influenzed by carbonate(CO2 from the air) it will be useable for indefined time.
tmeszaros on Jun 5 2010, 11:40 AM said:
I'm looking for som literature or something valid information about the shelf life of self prepared solvents. Generally if I make an 1 M NaOH solution, I shall give to exiry date 1 month after producing date? And in case of 1% CMC solutions (using as vehicle in toxicology research) shall I follow this 1 month as a main guide line? Unfortunatelly I'm new in this topic, and I don't have enough information about this. Can somebofy help me? THX!
solutions can be spoiled by microbial contaminations, CO2, O2, hydrophilic instability, thermal instability, wrong storing receptacle (f.i. 1M NaOH in glas receptacle) a.o.; so you have to check at least the possibilites of autoclaving or sterile filtration, freezing or degasing, repectively;
a 1M NaOH solution in plastic will be stable for months