Bacterial Plates and Condensation

[kiki06]

How can I prevent the condensation (water) build up after I make LB bacterial plates and put them in the fridge 4C??

[aftabac]

Hi Kiki
it is a common problem and we are also facing the same problem, the problem of water condensation persists but it can be reduced by following ways.
1 water condensation is more when you pour hot media in petriplates so try to pour the media when it is not very hot.
2 when you pour media then do not put the lid immediatly but stay it for 30min or so in laminar flow cabinet and then put the lid on the plates.
3 after solidification of media, seal the plates with parafilm carefully and then put the plates at 4 oC.
these precautions reduce the level of water condensation, and if someone has eliminated this situation completly then please write us.

regards
aftab ahmad

[tuttu]

Hi,

I generally leave my plates in room temperature overnight on the day I pour the plates and the following morning I store it in 4C fridge. I don get get the problem of water condensation in the plates.

[kiki06]

Tuttu thats smart.

Does this affect the antibiotics? I mean does penicillin degrade or lose its effectiveness at room temperature for that time?

I know we keep plates overnite in 37 degree incubator so it might not be a big problem...

thanks in advance

[kmunson779]

We store our plates agar-side up, so if condensation occurs it will pool on the lid of the plate. A quick shake of the lid into the trash and the water is effectively gone.

You do have to leave the plates out at room temp. long enough to solidify, but that doesn't take too long.

[molecule2005]

Hey Kmunson,
that is clever!

thanks all for the tips! my bacterial plates always get a flooding in the fridge!

[tuttu]

Hi Kiki,

I have worked with penicillin, and for wat i know these are stable for atleast 15 days in room temp and for a minimum of two months in the fridge. Contaminations to be taken care of @ RT!!

cheers

[kalaig]

Hi everyone!
Well it may involve many steps! first use the correct amount of agar 1.5% good quality agar, cool well; leave the lid half closed for an hour to solidify in lamiar flow; and invert the plates and store at 37C. Spread plating especially needs dry plates and leaving the UV on (if you can afford it may prevent air contamination!)