1. Laboratory of Physicochemistry of Interfaces UMR CNRS 5621 IFoS, Ecole Centrale de Lyon, B.P. 163, 69131 Ecully, France, Sector of Bioelectronics, Kiev University, P.O. Box 152, Kiev-1 252001, Ukraine, and Department of Experimental Medicine U INSERM 52, Cl. Bernard University, 8 avenue Rockefeller, 69373 Lyon, France