1. “Petru Poni” Institute of Macromolecular Chemistry; 700487 Iasi Romania
2. London Centre for Nanotechnology and Department of Physics and Astronomy University College London; Gower Street London WC1E 6BT United Kingdom
3. Laboratoire de Physicochimie des Polymères et des Interfaces (EA 2528), Institut des Matériaux; Université de Cergy-Pontoise; 5 Mail Gay Lussac F-95031 Cergy-Pontoise Cedex France