A new polycarbonate urethane (PCU-I) was synthesized from aliphatic monomers, i.e. polyhexamethylene carbonate diol and 4,4'-methylene-bis cyclohexane diisocyanate, a mixture of low molecular diols, and castor oil (containing mainly the triglyceride of 12-hydroxyoleic acid). The second synthesized polymer (PCU-II) did not contain castor oil. Both PCUs had good tensile strength, i.e. 32.5 and 27.8 MPa for PCU-I and PCU-II, respectively. Modification by castor oil led to a decrease in glass transition temperature (T(g) = -14 degrees C for PCU-I and -6 degrees C for PCU-II) and an increase in the softening temperature (135 and 125 degrees C for PCU-I and PCU-II, respectively). Partial crosslinking of PCU-I increased the storage modulus of elasticity and provided better resistance to sterilization by ETO and gamma radiation. Both PCUs displayed good stability when subjected to sterilization by hydrogen peroxide plasma. Neither PCU caused cytotoxic effect in mouse fibroblasts (3T3 Balb C). They also had no toxic effects on the morphotic components and did not influence changes in the hematologic parameters or plasmatic coagulation system of human blood.

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Preparation of gold nanoparticles stabilized by chitosan using irradiation and sonication methods 18 U. Filipkowska, M. Kuczajowska-Zadrożna, T. Jóźwiak, P. Szymczyk, A. Kaczyński Adsorption of Basic 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 Pervaporative investigation of ethyl alcohol drhydratation 54 B. Grimling, J. Meler, M. Szcześniak, J. Pluta, E. Górniak The study of physicochemical properties of solid dispersions of ibuprofen in the presence of chitosan 64 J. Ignacak, M. Wiśniewska-Wrona, J. Dulińska-Litewka, I. Pałka, M. Kucharska The role of oligochitosana in AKT kinase regulation 73 T. Jóźwiak, U. Filipkowska, P. Szymczyk, M. Kuczajowska-Zadrożna, A. Mielcarek Application of chitosan ionicaly crosslinked with sodium edetate for reactive dyes removal from aqueous solutions 82 E. Karuga, A. Zając, Z. Rybak, J. Hanuza New chitosan wound dressingfirst step-the cytotoxicity evaluation 97 E. Kopania, M. Wiśniewska-Wrona Application of galactoglucomannans (GGMs) extracted from spruce sawdust for stimulation of plant seeds germination 110 S. Książek, M. Mucha Thermal stability of chitosan nanocomposites containing TiO 2 and organomodified mantmorillonite

In this work, we describe a novel technique for producing biocompatible medical products with bioactive properties from the biodegradable polymer dibutyrylchitin (DBC). Materials produced by blowing out polymer solutions have excellent hemostaic properties and are easy to handle during surgery. Biocompatibility studies, encompassing hemostasis and the evaluation of post-implantation reactions, indicate that the biological properties of DBC depend on the molecular mass of the polymer. Lower molecular mass polymers are preferable for use in implanted wound dressings.

Investigations are presented for the preparation of a model hemostatic dressing that would exhibit an adequate hemostatic capacity in injuries and surgical wounds, an antibacterial activity to prevent primary and secondary infections, and offer safety in use. The Hemoguard dressing has been designed as a powder prepared from the complex chitosan/alginate Na/Ca in the form of micro- and nano-fibrids. Useful antibacterial and hemostatic properties of Hemoguard, which would qualify the material as first aid dressing and a temporary protection of injury wounds in field conditions, were assessed. Biocompatibility of the dressing was confirmed by biological in vitro examinations.

A knitted implant, unilaterally modified with plasma-assisted chemical-vapor deposition (PACVD), and with a nano-layer of fluorine derivative supplementation, for reducing the risk of complications related to adhesions, and the formation of a thick postoperative scar was prepared. The biological evaluation of designed or modified medical devices is the main aspect of preclinical research. If such studies use a medical device with prolonged contact with connective tissue (more than 30 days), biocompatibility studies require a safety assessment in terms of toxicity in vitro and in vivo, allergenicity, irritation, and cancerogenicity, reproductive and developmental toxicity. The ultimate aspect of biological evaluation is biofunctionality, and evaluation of the local tissue response after implantation, resulting in the determination of all aspects of local biocompatibility with the implemented synthetic material. The implantation of PACVD-modified materials in muscle allows us to estimate the local irritation effect on the connective tissue, determining the risk of scar formation, whereas implantation of the above-mentioned knitted fabric into the abdominal wall, assists with evaluating the risk of fistula formation—the main post-surgical complications. The research aimed to evaluate the local reaction of the soft tissues after the implantation of the knitted implants modified with PACVD of the fluoropolymer in the nanostuctural form. The local effect that occurred during the implantation of the designed implants was quantitatively and qualitatively evaluated when PACVD unmodified (reference), and modified medical devices were implanted in the abdominal cavity (intra-abdominal position) for 12 or into the muscles for 56 weeks. The comparative semi-quantitative histological assessment included the severity of inflammatory cells (multinucleated cells, lymphocytes, plasma cells, macrophages, giant cells) and the tissue response (necrosis, neovascularization, fibrosis, and fat infiltration) on a five-point scale. The knitted implants modified by PACVD did not indicate cumulative tissue response when they were implanted in the muscle and intra-abdominally with direct contact with the viscera. They reduced local tissue reaction (score −2.71 after 56 weeks of the implantation) and internal organ adhesion (irritation score −2.01 and adhesion susceptibility −0.3 after 12 weeks of the implantation) compared with the reference (unmodified by PACVD) knitted implant, which had an identical structure and was made of the same source.

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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