The Fluorophore 4′,6-Diamidino-2-phenylindole (DAPI) Induces DNA Folding in Long Double-Stranded DNA (pages 1803–1810)
Dr. Maria Rosa Beccia, Dr. Tarita Biver, Alberto Pardini, Jacopo Spinelli, Prof. Fernando Secco, Prof. Marcella Venturini, Dr. Natalia Busto Vázquez, Prof. Maria Pilar Lopez Cornejo, Victoria Isabel Martin Herrera and Prof. Rafael Prado Gotor
Version of Record online: 21 MAY 2012 | DOI: 10.1002/asia.201200177
Building bridges: DAPI is a widely used fluorescent dye, whose complicated binding features to DNAs and RNAs are still not fully understood. In this study, T-jump kinetic analyses, melting experiments, as well as viscometric, binding equilibria, and circular dichroism measurements concur in shedding light on the complex DAPI/DNA interactions, which can change from groove binding to intercalation. Moreover, it is observed for the first time that DAPI is able to induce the formation of a rather compact polymer–dye adduct stabilized by DAPI bridges.