Making of alkaline lysis solution - Funny white colouratio of lysis solution (Sep/15/2009 )

Hi all,

I tried making an alkaline lysis solution (0.2N NaOH, 1% SDS) for bacmid isolation. I filtered sterilized it and stored it in a 50 ml falcon tube. After some time, the transparent solution turned white (turbid) for some unknown reason. I thought it was dissolving the plastic so I transferred it to a glass bottle. But it is still turbid until now.

I know that is alkaline lysis solution is the same as buffer P2 for qiagen miniprep and theirs don't look white. I wonder what is the problem or is there any 'trick' in making this solution.

Thanks!

I was taught to always make mine fresh just before I use it. Takes less than 30 seconds to do (I keep the components sterile in seperate bottles on my bench).
It is the SDS precipitating out of your solution. You could try warming it up and redissolving your SDS prior to use if you had your heart set on making the solution ahead of time.

If you are storing it below room temperature, the SDS will precipitate out. It will go into solution on warming.

Not aware of the concentration you're using but SDS is highly soluble - to ~ 10% aq. (http://www.jtbaker.com/msds/englishhtml/s3670.htm)
les so at low temp's, as leelee said.
Not aware that it should be less soluble in a dilute alkaline solution with nothing else in solution.

You may be seeing precipitation of sodium carbonate.

Hi all,

Thanks a lot for all the ideas/suggestions! I will just warm up my lysis solution everytime before using it. Actually like leelee said I think I should really make them fresh each time before usage.