Nanoparticles have a great prospect for therapeutic applications. They can protect drugs under physiological conditions and act as a matrix for directed delivery of drugs, e.g., to a specific tissue or cell type. Polymer-based nanomaterials are considered as highly effective in this regard. Their properties can be tailored to meet specific demands for given therapeutic purposes. Considering the high-quality standards placed on medical products, the question arises: Which type of polymer material should be employed? One might select synthetic polymer compounds, which are highly diverse in terms of the molecular structures and supramolecular architectures that can be created, or biopolymers such as polysaccharides that are renowned for their native biocompatibility.