Fig. 3

AFM analysis of PAMAM-BDNF (above part) and PEG-ylated PAMAM-BDNF (below part) nanoparticles adsorbed at mica surface at 0.15 M pH 7.4: PBS. a PAMAM-based nanoparticles at a scan area of 0.5 × 05 µm. b Structure of PAMAM-based nanoparticles after cross-section. c Histogram of adsorbed nanoparticles indicated by direct AFM enumeration, obtained for a low surface molecules concentration. The figure was created by taking into account 10 randomly chosen areas, where each micrograph of PAMAM-based monolayer at the mica surface has a size of 0.5 × 05 µm