Modified alginates have a wide range of applications, including in the manufacture of dressings and scaffolds used for regenerative medicine, in systems for selective drug delivery, and as hydrogel materials. This literature review discusses the methods used to modify alginates and obtain materials with new or improved functional properties. It discusses the diverse biological and functional activity of alginates. It presents methods of modification that utilize both natural and synthetic peptides, and describes their influence on the biological properties of the alginates. The success of functionalization depends on the reaction conditions being sufficient to guarantee the desired transformations and provide modified alginates with new desirable properties, but mild enough to prevent degradation of the alginates. This review is a literature description of efficient methods of alginate functionalization using biologically active ligands. Particular attention was paid to methods of alginate functionalization with peptides, because the combination of the properties of alginates and peptides leads to the obtaining of conjugates with properties resulting from both components as well as a completely new, different functionality.

This work presents the results of research on obtaining chitosan (CS) films containing on their surface ciprofloxacin (CIP). A unique structure was obtained that not only gives new properties to the films, but also changes the way of coverage and structure of the surface. The spectroscopic test showed that in the process of application of CIP on the surface of CS film, CIP was converted from its crystalline form to an amorphic one, hence improving its bioavailability. This improved its scope of microbiological effect. The research was carried out on the reduction of CIP concentration during the process of CIP adhesion to the surface of chitosan films. The antibacterial activity of the CS films with and without the drug was evaluated in relation to Escherichia coli and Staphylococcus aureus, as well as Candida albicans and Penicillium expansum. Changes in the morphology and roughness of membrane surfaces after the antibacterial molecule adhesion process were tested with atomic force microscopy (AFM) and scanning electron microscopy (SEM). Structural analysis of CS and its modifications were confirmed with Fourier-transform spectroscopy in the infrared by an attenuated total reflectance of IR radiation (FTIR-ATR) and solid-state nuclear magnetic resonance (NMR).

Physical and chemical modifications of chitin and chitosan allow for obtaining new functional properties of the natural polymers. This is a particularly valuable feature for the design and manufacture of new materials for medical applications. Due to their wide and varied biological activity, chitin and chitosan materials are increasingly used as dressing materials with antibacterial and hemostatic properties and as materials accelerating the regeneration of damaged tissues because of stimulation of granulation tissue formation, re-epithelialization and reduction of the formation of scar tissue. In addition, chitosan derivatives have antifungal, antiviral, anticancer activity. The increasing use of chitin and chitosan also has a positive impact on the environment, as it is obtained as a result of chitin deacetylation, usually isolated from shellfish shells. The main source of chitin is waste coating of crustaceans. The annual natural reproducibility of chitin by biosynthesis is estimated at 2–3 billion tons. Our interest in the use of biodegradable biopolymers derived from chitin concerns the design, synthesis in laboratory scale, testing new material properties and the final implementation of new developments for industrial practice of new dressing materials useful in the treatment of bleeding wounds (haemostatic properties) as well as in the regeneration of wounds and ulcers of various etiologies. Examples of chitin-based dressing materials introduced by Tricomed SA are Medisorb R Ag, Medisorb R Membrane, Medisorb R Powder and Tromboguard®.