MTT and disolving's problem - (Jan/26/2007 )

Hello,

I realise some MTT test on mycobacteria's cultur and I have some problem to disolve completely my formazan.
I have a volume of 200µl/ well.
- Add 10µl/well of MTT solution (5g/l), Incubate 0/N at 37°C
- Add 50µl/well of SDS 20%/ 50% DMF (1:1) or 10% SDS/ 0,1N HCl and incubate O/N at 37°C
But after one night all my cristals are not completely disolve.

Do you know where is the problem or what can I do or use to improve my experiment???

Thanks a lot

biofred

Hi Biofred,

So when I do a MTT assay, I add 1/10 of MTT 5mg/ml in a medium without phenol red (for you 20 µl of MTT), incubation 2 hours at 37°C, remove the medium and add DMSO, mix gently few minutes before reading the absorbance at 540nm with backgroung at 650nm.