Synthesis and Characterization of Antibacterial Chitosan Films with Ciprofloxacin in Acidic Conditions.

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).

Modification of Alginates to Modulate Their Physic-Chemical Properties and Obtain Biomaterials with Different Functional Properties.

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.

Study on the Materials Formed by Self-Assembling Hydrophobic, Aromatic Peptides Dedicated to Be Used for Regenerative Medicine.

The aims of this study were to identify the short aromatic peptides which are able to form highly ordered amyloid-like structures in self-assembling processes, to test the influence of length of hydrophobic peptides on tendency to aggregation, and to check if aggregated peptides fulfill requirements expected for materials useful for scaffolding. All tested hydrophobic peptides were prepared on solid phase by using DMT/NMM/TsO- as a coupling reagent. The progress of aggregation was studied by set of independent tests. All aggregated peptides were found stable under in vitro conditions. All fibrous material formed by self-assembling of peptides does not show any cytotoxic effects on L929 fibroblast cells. Peptides containing tyrosine and tryptophan residues even effectively accelerated the proliferation and stimulated the activity of L929 fibroblasts.