We are pursuing the aim to use DNA as a supramolecular scaffold for the creation of electronically functional molecules on the nanometre scale. Here, we give a review on our results on porphyrin modified nucleotides used for this purpose. A general synthetic route to porphyrin-nucleotides has been devised, and the building blocks can be incorporated into oligonucleotides using standard solid phase synthesis methods. Up to 11 porphyrins were incorporated into DNA, reaching a length of approximately 4 nm in the array. The spectroscopic data are consistent with a porphyrin induced secondary structure stabilisation in the single strands.