Jahir I think u need to use EDTA-tris to protect the DNA from decaying

Thanks dada for your information but how many days it will keep the DNA normal? Do you have any idea? 

Hi Zohorul!

There is no problem keeping your bacterial genomic DNA by boiling method for furhter investigation. I usually storage them for a good time at -70 or -80 and have afterwards a good PCR result!

Good luck!

Dear Zohorul,

if you add to your DNA Tris-HC pH 7.8-8.5 at a final concentration of 10 mM and EDTA at a finale concentration of 1 mM, your DNA  will be stable for years or decades at -20°C, whereas if you keep at 4°C it will be stable for several months, and at room temperature for several days.

Thanks Norma Suely and Enrico Baruffini for your contribution.