Abstract:
We report the synthesis of two new amphiphilic
conjugates 1 and 2 based on naphthalene di- and monoimide
chromophores and the investigation of their photophysical,
self-assembly and DNA-binding properties. These
conjugates showed aqueous good solubility and exhibited
strong interactions with DNA and polynucleotides such as
poly(dG·dC)–poly(dG·dC) and poly(dA·dT)–poly(dA·dT). The
interaction of these conjugates with DNA was evaluated by
photo- and biophysical techniques. These studies revealed
that the conjugates interact with DNA through intercalation
with association constants in the order of 5–8Õ104m¢1. Of
these two conjugates, bolaamphiphile 1 exhibited a supramolecular
assembly that formed vesicles with an approximate
diameter of 220 nm in the aqueous medium at a critical
aggregation concentration of 0.4 mm, which was confirmed
by SEM and TEM. These vesicular structures showed a strong
affinity for hydrophobic molecules such as Nile red through
encapsulation. Uniquely, when exposed to DNA the vesicles
disassembled, and therefore this transformation could be
utilised for the encapsulation and release of hydrophobic
molecules by employing DNA as a stimulus.
