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Tris-Hcl becomes cloudy. - (Feb/07/2012 )

Hello People,

I was preparing 1.5M Tris-Hcl pH 8.8, and the solution is cloudy, which I don't understand why. I tried to make it with distilled water & MilliQ H2O, the same. I tried to increase the temperature to 35deg C and dissolve, but still the same. pH was maintained at 8.8 throughout. I also put the solution under stirrer for a whole night and still the same. I didn't add any NaOH at all.
When I used this Tris-Hcl to run my buffer, the electrophoresis was fine. And even the Western Blot turned out pretty good.
But I don't understand the reason for the buffer to be still cloudy. Can anyone explain? Thanks.


There could be a number of reasons - 1) it could be that your bottle(s) are dirty and something (perhaps detergents) are coming off into solution. 2) it could be that there is a contaminant in the Tris or (less likely) the HCl. 3) it could be that your MilliQ filters need to be changed as something is coming through. I have seen this before when someone cleaned the distiller for the water that supplied the MilliQ by rubbing off the calcium build up and not flushing the line before re-connecting it to the supply.


may be therevis contamination


may be there is contamination