Cloudy destaining solution...why! - (Jun/13/2008 )

Hi,

I'm having so much trouble preparing the destaining solution to destain my gel (stained with biorad coomassie blue).

After I've added 40% methanol + 7% acetic acid and topped up with dH2O (to make 1L), the solution started to get cloudy during the addition of dH2O. The destaining solution did not turned clear after left standing overnight without disturbance.
I'm wondering if anyone of you has faced this problem before?

Desperately need help as I can't destain my gel and it has been 4 days already!!!!

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Never had this problem, can't you change your Methanol or Acetic Acid and get from other labs?

are you sure about the pH of your dH2O? is it clean? can you filter your destaining solution?

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Hmm....but how would the pH of the dH2O caused the cloudiness of the destaining solution?

I've actually tried making smaller volume of the destaining solution (i.e 10ml) with the same proportion of the acetic acid, methanol and dH2O, same results were obtained as previous. However, the destaining solution turned clear after left standing overnight. Now that's the most puzzled part when my 1L of destaining solution did not turned clear after left standing overnight.

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yes, sometimes the distilled water has different pH due to the quality of the tap water or the quality of the water of the region you are from....because this has happened to us many times.

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wow! So I've to make sure that the pH of the dH2O is neutral?

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you probably have something coating your labware.

make sure it is clean and then rinsed with dw.

btw, we use 30% methanol, 5% acetic acid to destain our gels.

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