High levels of maximal BSA adsorption onto silica-based cationic bilayers. BSA adsorption isotherms onto silica/DODAB particles in two different media. 1 mM NaCl, pH 6.3 or 5 mM Tris.HCl, pH 7.4. Open and filled circles refer to two independent experiments with each mixture evaluated in duplicate. Interaction between silica/DODAB particles and protein took place for 1 h at 25°C. Final silica and DODAB concentrations are 0.1 mg/ml and 0.05 mM, respectively. BSA adsorption was expressed as adsorbed BSA concentration in mg/ml (A and C) or as number of BSA molecules adsorbed per m2 silica (B and D).