Template and catalytic effects of DNA in the construction of polypyrrole/DNA composite macro and microelectrodes

► Growth of polypyrrole is affected by the presence of guanine in ssDNA probes. ► Amplification effect is lost with double-stranded DNA. ► Caution should be taken to avoid DNA oxidation during PPy growth. ► We also report a method for developing PPy/DNA microelectrode arrays. ► We show that SECM is a suitable technique for imaging these arrays.