**2.1 Reagents**

Polyvinylpyrrolidone (PVP, MW 360 kDa) was obtained from Sigma-Aldrich (St Quentin Fallavier, France). Poly(L-Lysine)-PEG (PLL(20KDa) grafted with PEG(2 Kda) having 3.5 Lys units/PEG chains = PLL-PEG) was purchased from SurfaceSolutionS (Zurich, Switzerland).

Peptides were synthesized by Altergen (Bischheim, France) with a pyrrole-modified NH2 terminus as previously described (Villiers et al., 2009). Two peptides are derived from the structural protein core of hepatitis C virus of the genotype 1b (HCV), one from ovalbumine, one from hen egg lysozyme, nine from hepatitis D virus (HDV) of various genotypes. Full sequences can be found on the ExPASy server (http://ca.expasy.org/) under different accession numbers (Table 1).


Table 1. Peptides used in the study

Rabbit immune serums against different peptides were prepared by NeoMPS (Strasbourg, France). Human serums from healthy donors as non immune serum (NIS) were purchased from the Etablissement Français du Sang (La Tronche, France). Human serums from HDV infected patients were provided by Drs E. Gordien and S. Brichler (Hôpital Avicenne, Paris, France) and Dr P. Morand (Centre Hospitalo-Universitaire, Grenoble, France). Serums were stored at -20°C.
