27 th ECIS Conference 1 - 6 September 2013, Sofia, Bulgaria Monitoring the Interaction of Nucleolipoplexes with Model Membranes Piero Baglioni*, Debora Berti, Costanza Montis Department of Chemistry University of Florence and CSGI, Via della Lastruccia 3, Sesto Fiorentino, 50019, Firenze Italy * - piero.baglioni@unifi.it A full exploitation of the potential of nanostructured devices as drug delivery systems is still hampered by a substantial lack of robust physico-chemical approaches to predict and model the fundamental interactions with biologically relevant media or interfaces, such as biological membranes.[1] We present an investigation on the interactions of complexes between nucleolipid liposomes and DNA (Nucleolipoplexes),[2-3] with Giant Unilamellar Vesicles (GUVs),[4] meant as structural mimics of cell membranes. For the first time, Laser Scanning Confocal Microscopy (LSCM) and Fluorescence Correlation Spectroscopy (FCS) are combined to fully characterize the internal morphology and mesostructure of the Nucleolipoplexes. Their interaction with GUVs is monitored with the same techniques, providing evidence of that the liquid crystalline of the complexes and the surface charge density target membrane model affect the delivery process. Finally, FCS was for the first time employed for the structural characterization of lipid membranes fusion intermediates. Literature: [1] D.Berti, G. Caminati, P. Baglioni, PCCP, 2011, 13, 19, 8769-8782. [2] S. Milani, G. Karlsson; K.Edwards, P. Baglioni, D. Berti, Journal of Colloid and Interface Science , 2011, 363, 232–24. [3] C. Montis; S. Milani; P. Baglioni, D. Berti, Journal of Colloid and Interface Science, 2012, 373, 57-68. [2] S. Nappini, T. Al Kayal, D. Berti, B. Norden, P. Baglioni, J. Phys. Chem. Letters, 2011, 2, 713-718. Acknowledgements: Thanks are due to Miur (Prin 2010) for financial support.