Long-term antimicrobial effect of polylactide-based composites suitable for biomedical use

This work deals with the preparation and characterization of antimicrobial polymeric composite materials based on polylactide, which is currently widely investigated to produce temporary implants. Polylactide was blended with antimicrobial fillers: silver, hexadecylpyridinium or hexadecyltrimethylammonium bromides anchored on vermiculite or graphene oxide matrices in an amount of 1% wt. The prepared samples were characterized by conventional methods, further they were exposed to degradation tests in physiological saline conditions and characterized for their antimicrobial properties using common pathogen microorganisms. It has been proven that the prepared polylactide composites change their antimicrobial effects after being in physiological saline of pH 7 and 9 for 0–6 months. The weight of the composites changed by about 10%, and antimicrobial properties were growing over time. The effectiveness of the composites was confirmed for 6 months at minimum. Therefore, they are suitable for the preparation of temporary stents, catheters or implants suitable for fracture fixation. © 2022 The AuthorsEuropean Commission, EC: LINKA20364; Ministerstvo Školství, Mládeže a Tělovýchovy, MŠMT; Consejo Superior de Investigaciones Científicas, CSIC: CZ.02.2.69/0.0/0.0/19_073/0016945, DGS/INDIVIDUAL/2020-00

Chemical Hydrogels Bearing Thiazolium Groups with a Broad Spectrum of Antimicrobial Behavior

© 2020 by the authors.Several hydrogels based on 2-hydroxyethyl methacrylate and a methacrylic monomer containing a thiazole group in its lateral chain have been prepared by thermal polymerization at 60 °C in water solution varying the chemical composition of the gels. The posterior quaternization of the thiazole groups with methyl iodine has rendered positively charged hydrogels with potential antimicrobial activity. This modification has been structurally characterized by infrared spectroscopy, whereas the thermal stability of all hydrogels has been studied by thermal degradation in inert atmosphere. The swelling behavior in distilled water and the rheology of the different hydrogels have been analyzed as a function of 2-(4-methylthiazol-5-yl)ethyl methacrylate (MTA) monomer content as well as its methylation. Finally, the active character of hydrogels against Gram-positive and Gram-negative bacteria and fungi has been evaluated, revealing excellent antimicrobial activity against all tested microorganisms. The methylated hydrogels could be used as potential materials for wound healing or contact lens applications.This work was funded by the CSIC (i-LINK4911), MINECO (Project MAT2016-78437-R), MICINN (PID2019-104600RB-I00), the Agencia Estatal de Investigación (AEI, Spain) and Fondo Europeo de Desarrollo Regional (FEDER, EU) and by Ministry of Education of the Czech Republic through the SGS project SP2020/70 and project No. CZ.02.1.01/0.0/0.0/17\_049/0008441 “Innovative Therapeutic Methods of Musculoskeletal System in Accident Surgery” within the Operational Programme Research, Development, and Education.Peer reviewe