PCR positive control of antibiotics resistance gene - (Oct/25/2016 )

Hi, I'm trying to PCR some antibiotics resistance genes from food samples using my own primers, so I need a positive control to validate these primers. Where can I purchase these positive control DNA?

Thank you very much.

PL

Most plasmids contain at least one antibiotic resistance gene so that you can select bacteria that contain the plasmid over those that don't. Try Addgene for plasmids, otherwise you can purchase them from a wide range of suppliers.