Two 1530-nm emitting co-polymers have been synthesized by incorporating differently substituted erbium-porphyrin complexes into the conjugated backbone of a polyaryleneethynylene structure. While the near infrared (NIR) emission exhibits the typical narrow width of lanthanide ions, the absorption and excitation spectra are quite broad and extend in the red range more than in any other organo-lanthanide molecule. This indicates that highly pi-conjugated systems are effectively formed. For both polymers, however, the quantum efficiency is as low as in the isolated complexes, which suggests that the increased conjugation does not influence the intramolecular transfer and the quenching processes of the erbium ion. (c) 2006 Elsevier B.V. All rights reserved.