Influence of perylenediimide-pyrene supramolecular interactions on the stability of DNA-based hybrids: Importance of electrostatic complementarity

Aromatic pi-pi stacking interactions are ubiquitous in nature, medicinal chemistry and materials sciences. They play a crucial role in the stacking of nucleobases, thus stabilising the DNA double helix. The following paper describes a series of chimeric DNA-polycyclic aromatic hydrocarbon (PAH) hybrids. The PAH building blocks are electron-rich pyrene and electron-poor perylenediimide (PDI), and were incorporated into complementary DNA strands. The hybrids contain different numbers of pyrene-PDI interactions that were found to directly influence duplex stability. As the pyrene-PDI ratio approaches 1:1, the stability of the duplexes increases with an average value of 7.5 degrees C per pyrene-PDI supramolecular interaction indicating the importance of electrostatic complementarity for aromatic pi-pi stacking interactions.