I acquired the plasmid in Addgene, reconstituted the filter paper where the plasmid comes from with 30 microliters of TE buffer pH 8, immediately afterwards perform the transformation of E.coli DH5 alpha bacteria using the heat shock method and LB medium with ampicillin (100 ug / mL). After incubating 24 hours at 37 ° C, I did not obtain positive colonies. Somebody could help me?