Nanoparticles which have irregular shapes were scattered on the surface. The Observed diameters of nanoparticles were less than 300 nm (Fig. 3(e)). This presents a contradiction between the AFM and TEM data on chitosan NPs diameter as AFM suggested that the diameters of nanoparticle are less than 25 nm. However, this discrepancy could be explained by careful analysis of the TEM images. In certain locations isolated patches of chitosan NPs due to much smaller diameters (less than 30 nm) could be observed (Fig. 4). We could expect that these nanoparticles act as building blocks for large nanoparticles that were frequently observed in the sample. Single nanoparticles could be identified as composed of a number of smaller nanoparticles which are produced during sonication of chitosan nanofibers (Fig. 3(f)).