Résumé
Water-soluble π-conjugated polymers offer new perspectives as nanomaterials for biosensing and biomedical imaging. A series of cationic conjugated polymers were studied for DNA optical detection, for example to detect DNA lesions or single-nucleotide polymorphisms (SNPs), which is of great interest for genomic applications. The fundamental understanding of structural aspects of DNA/conjugated polymers complexes in aqueous and physiological solutions is key for the development of relevant biosensors. This chapter aims at providing a new perspective on DNA/conjugated polymer assemblies at the supramolecular level, by deciphering the effects of DNA sequence and related conformational changes and aggregation processes occurring upon the self-assembly of DNA with cationic polythiophenes. By combining (chir)optical spectroscopy and molecular modelling simulations, we provide helpful structural insights in the context of DNA hybridization biosensors, with an example applied to the detection of single nucleotide mismatch.