Want PCR to incorporate 32P label

[Manuel Maria SIMON]

smori at nmsu.edu (Shahram Mori) wrote:
>
> PAUL JONES (jone3 at essex.ac.uk) wrote:
>  Has anyone had success with incorporation of 32P dNTP into an extending strand
>  in PCR for northern/ southern hybridisation?  I would have thought is would 
>  give 
>  higher signal / noise ratio than probes produced by random hexamer method 
>  and a method of choice for probes <200 bp.
> 
>  Hope there is opinion out there.
> 

Hi Paul

I did PCR labelling successfully. I amplified some 0,5 ng 
(or less) plasmid in a normal buffer system (e.g.1,5 mM Mg++). 
Instead of the 100 microM dNTP I used 5 in each except the 32P-dCTP
(3000 Ci/mmol from NEB), which is usually 50 microCi.
Then a 20 cycle PCR was done in conditions where I knew that the
fragment was properly amplified, e.g. as a single and expected band.