No abstract

Bone repair or regeneration is a common and complicated clinical problem in orthopedic surgery. The importance of natural polymers, such as microcrystalline chitosan, and minerals such as HAp and β-TCP, has grown significantly over the last two decades due to their renewable and biodegradable source, increasing the knowledge and functionality of composites in technological and biomedical applications. This study compares the biodegradation process, bioactivity, structure, morphology, and mechanical properties of microcrystalline chitosan and microcrystalline chitosan/β-TCP complex; the latter according to the new method of preparation. The complex showed a homogeneous network structure with regular pores, good bioactivity, even after 60 days of conducting the hydrolytic and enzymatic degradation process, showing a bacteriostatic and bactericidal activity. The complex indicates that it could be used successfully as a base for implants and scaffolds production in orthopedic surgery.

Designing medical devices requires a wide range of verification steps for estimation of the performance and safety. Designing the research program needs a rational selection of appropriate testing methods (in preclinical and clinical studies) for determination of the risk of potential incompatibilities resulting in adverse events. The significance of the appropriate selection of the testing method is increased in advanced medical devices. The presented research considers the verification of the functional properties of recently developed topical haemostatic agents with the use of the chitosan/alginate fibrids, based on the previously elaborated risk analysis made according to the guidelines of the PN-EN-ISO 14971:2012 and PN-EN ISO 22442-1:2008 standards. The aim of this research was to verify the stability of the performance of the newly developed haemostatic agents during storage. The defined aim of the study arose from the thesis that the appropriate selection of raw materials and a new manner of reprocessing them enabled keeping the usability of the final product for at least two years.

Designing usable forms of topical haemostatic agents is the most important activity during the design process, resulting in strengthened functional properties of the final medical devices. This study aimed to propose indications for a research programme based on risk management supporting the development of two usable forms of a topical haemostatic agent: chitosan/alginate lyophilized foam and chitosan/alginate impregnated gauze. Both of the usable forms of the topical haemostatic agent, being the main part of the modified combat gauze, were fabricated using the chitosan/alginate complex. Risk analysis is helpful in developing an appropriate research programme, significantly reducing the risk to an acceptable level.

Yellow 28 (BY 28) and acid Yellow 23 (AY 23) dyes onto chitin 34 M. Gierszewska-Drużyńska, J. Ostrowska-Czubenko Structural and swelling properties of hydrogel membranes based on chitosan crosslinced with glutaraldehyde and sodium tripolyphosphate 43