Two strategies of DNA biochip construction on conducting polymers are inves
tigated. The first involves a direct electro-copolymerization of pyrroleoli
gonucleotides (oligonucleotides tethered to a pyrrole group) with the pyrro
le leading to a polypyrrole film bearing the oligonucleotides. Successive c
opolymerizations allow the transformation of a microelectrode array into a
DNA array. The second methodology involves a direct in situ synthesis of ol
igonucleotides on a conducting polymer used as an organic electrode. In thi
s way a 5' electrolabile protecting group, p-nitrobenzoyl, was used. In ord
er to construct short oligonucleotide sequences, the other protecting group
s of the bases have also to be modified, preliminary results based on this
technology are shown.