Hi.

Heat up to 60~65C for 30 min.

Try other protocols in which you add necessary volumes of CTAB sol and SDS sol to the sample separately. CTAB needs warning up to dissolve evenly to obtain a precise concentration, in particular, after storage, too.

Regards.

Dear Yugendran,

watch out for any sources of potassium (e.g. PBS buffers) as they precipitate with SDS.

Cheers Markus

Hi, I don't know why you would want to make a SDS/CTAB solution, but Sang and Markus are correct. Heat the solution and avoid any cations except Na+

Is it normal to get a white precipitate after addition of SDS to CTAB buffer?

This is my CTAB ingredients:

1.) 100 mM Tris-HCL, pH 8

2.) 100 mM EDTA, pH 8

3.) 100 mM Sodium phosphate monobasic, pH 8

4.) 1.5 M NaCl

5.) 2 % CTAB

Hi Shi, I know that SDS forms precipitates with K+ and guanidinium. Maybe it is forming precipitates with CTAB. This can be easily tested.

If CTAB and SDS form precipitates then you will have to use another detergent for your sample.

Hello Steingrimur Stefansson ,

Thanks for your reply! Yes, the white precipitate remains even at 65 degrees celsius for an hour. It is just strange because I have read in many papers that SDS is used in combination with CTAB for DNA extraction from sediments.

So I am not sure if this observation is something I should see.

Thanks!

Shi Ming