DNA liquid crystals doped with AuAg nanoclusters: One-photon and two-photon imaging

Many essential similarities between the behavior and arrangement of biological structures and liquid crystals can be found. Moreover, some of biomacromolecules, such as DNA, are shown to exhibit lyotropic liquid crystalline phases both in vitro and in vivo. In this study, we used natural DNA concentration condition to form DNA liquid crystal (LC) phases as a simplified in vitro model of DNA self-ordering in cells. Due to the increasing interest in the use of nanoparticles as optical markers, we investigated possible applications of silver-doped gold nanoclusters (AuAgNCs) for one- and two-photon imaging in condensed DNA samples. We studied the influence of NCs doping on the DNA LC properties and the distribution of NCs within the liquid crystalline matrix. Depending on the type of DNA liquid crystalline phase we observed different emission patterns of AuAgNCs correlated with the degree of DNA ordering.