Mg2+-mediated self-assembly of an amphiphilic pyrene derivative with single-stranded DNA

An amphiphilic ethynyl-pyrene derivative modified with phosphonic acid groups (PyTOH) was synthesized and characterized. Single-stranded DNA (ssDNA), which carries negative charges, was found to induce the self-assembly of PyTOH through electrostatic interactions with Mg2+ as co-complexation ion in aqueous solution. UV-vis, fluorescence, and circular dichroism (CD) spectra revealed that left-handed helical architecture of PyTOH/Mg2+/DNA was formed. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) showed that nanoscale structures could be fabricated by self-assembly. (C) 2008 Published by Elsevier Ltd.