problem wiht long pcr fragment - (Nov/09/2005 )

I have a problem with my PCR. I would like to amplify PCR fragment (2 kb) from plasmid DNA. The problem is, sometime I get a weak band of PCR product but almost time I don't get any product.

Could you please suggest me, How can I do?

Thank you very much

Without more detail the best I can do is suggest you go back to a PCR where you had some amplimer and just re-amplify from that instead of going back to the original plasmid...

If you need to amplify long PCR products its better to use high fidelity taq but pleaseet me know if it worked with you