Procédé de fabrication d'un nanomatériau ayant des propriétés antibactériennes, matériau à base de celui-ci, et son utilisation

Method for manufacture of a nanocomposite material with antibacterial properties comprising mixing of a polymer and a filler, while the amount of the filler in the mixture is max 10% wt, and the polymer is selected from polyamide, acrylics, butadiene, dialkylphtalate, dimethylsiloxanes, isoprene, isobutylene, styrene structural units and the filler is hydrophobic carbon quantum dots hCQD which are prepared by bottom-up condensation reaction of polyoxyethylene-polyoxypropylene-polyoxyethylene. Nanocomposite material is adapted to cause an oxidative stress and reduce viability of bacteria, while the controlled antibacterial activity is activated after its illumination with blue light in the visible region having a wavelength of 420 - 470 nm.L'invention concerne un procédé de fabrication d'un matériau nanocomposite ayant des propriétés antibactériennes, comprenant le mélange d'un polymère et d'une charge, la quantité de la charge dans le mélange étant au maximum de 10 % en poids, et le polymère étant choisi parmi le polyamide, les acryliques, le butadiène, le dialkylphtalate, les diméthylsiloxanes, l'isoprène, l'isobutylène, les unités structurelles de styrène et la charge étant composée de points quantiques de carbone hydrophobes hCQD qui sont préparés par réaction de condensation ascendante de polyoxyéthylène-polyoxypropylène-polyoxyéthylène. Le matériau nanocomposite est conçu pour provoquer un stress oxydatif et réduire la viabilité des bactéries, tandis que l'activité antibactérienne contrôlée est activée après son éclairage avec une lumière bleue dans la région visible avec une longueur d'onde de 420 à 470 nm.Date of publication and mention of the grant of the patent: 27.01.2021 Bulletin 2021/04; Application number: 18719324.8, Date of filing: 27.02.2018; International application number: PCT/SK2018/050004; International publication number: WO 2018/160142(07.09.2018 Gazette 2018/36); European Patent Office: EP3589682, Date: 27.01.2021

Electrically conductive, transparent polymeric nanocomposites modified by 2D Ti3C2Tx (MXene)

The electrically conductive, transparent, and flexible self-standing thin nanocomposite films based on copolyamide matrix (coPA:Vestamelt X1010) modified with 2D Ti3C2Tx (MXene) nanosheets were prepared by casting and their electrical, mechanical and optical properties and then, were investigated. The percolation threshold of the MXene filler within the coPA matrix was found to be 0.05 vol. %, and the highest determined electrical conductivity was 1.4 x 10(-2) Scm(-1) for the composite filled with 5 wt. % (1.8 vol. %) of MXene. The electrical conductivity of the as-prepared MXene was 9.1 Scm(-1), and the electrical conductivity of the MAX phase (the precursor for MXene preparation) was 172 Scm(-1). The transparency of the prepared composite films exceeded 75%, even for samples containing 5 wt. % of MXene, as confirmed by UV spectroscopy. The dynamic mechanical analysis confirmed the improved mechanical properties, such as the storage modulus, which improved with the increasing MXene content. Moreover, all the composite films were very flexible and did not break under repeated twisting. The combination of the relatively high electrical conductivity of the composites filled with low filler content, an appropriate transparency, and good mechanical properties make these materials promising for applications in flexible electronics.Qatar University Collaborative High Impact Grant [QUHI-CENG-18/19-1

Electrically conductive, transparent polymeric nanocomposites modified by 2D Ti3C2Tx (MXene)

The electrically conductive, transparent, and flexible self-standing thin nanocomposite films based on copolyamide matrix (coPA:Vestamelt X1010) modified with 2D Ti3C2Tx (MXene) nanosheets were prepared by casting and their electrical, mechanical and optical properties and then, were investigated. The percolation threshold of the MXene filler within the coPA matrix was found to be 0.05 vol. %, and the highest determined electrical conductivity was 1.4 × 10-2 S·cm-1 for the composite filled with 5 wt. % (1.8 vol. %) of MXene. The electrical conductivity of the asprepared MXene was 9.1 S·cm-1, and the electrical conductivity of the MAX phase (the precursor for MXene preparation) was 172 S·cm-1. The transparency of the prepared composite films exceeded 75%, even for samples containing 5 wt. % of MXene, as confirmed by UV spectroscopy. The dynamic mechanical analysis confirmed the improved mechanical properties, such as the storage modulus, which improved with the increasing MXene content. Moreover, all the composite films were very flexible and did not break under repeated twisting. The combination of the relatively high electrical conductivity of the composites filled with low filler content, an appropriate transparency, and good mechanical properties make these materials promising for applications in flexible electronics.Author Contributions: Conceptualization, I.K. and M.M.; methodology, I.K. and P.S.; software, P.S.; validation, P.S. A.T.; formal analysis, P.S., Z.S., M.M, and Ma.M.; investigation, A.T., P.S., M.M., Ma.M., J.P. and A.P.; resources, I.K.; data curation, P.S., J.P., I.K., Ma.M., and M.M.; writing—original draft preparation, A.T., P.S., M.M. and Z.S.; writing—review and editing, I.K., M.M. and P.S.; visualization, P.S., J.P. and A.P.; supervision, I.K.; project administration, I.K.; funding acquisition, I.K.; Funding: This publication was supported by Qatar University Collaborative High Impact Grant QUHI-CENG-18/19-1. The findings achieved herein are solely the responsibility of the authors

Antibacterial potential of electrochemically exfoliated graphene sheets

Electrochemically exfoliated graphene is functionalized graphene with potential application in biomedicine. Two most relevant biological features of this material are its electrical conductivity and excellent water dispersibility. In this study we have tried to establish the correlation between graphene structure and its antibacterial properties. The exfoliation process was performed in a two electrode-highly oriented pyrolytic graphite electrochemical cell. Solution of ammonium persulfate was used as an electrolyte. Exfoliated graphene sheets were dispersed in aqueous media and characterized by atomic force microscopy, scanning electron microscopy, Raman spectroscopy, Fourier transform infrared spectroscopy, X photoelectron spectroscopy, X-ray diffraction, electron paramagnetic resonance, zeta potential, contact angle measurements and surface energy. Antibacterial assays have shown lack of the significant antibacterial activity. Major effect on bacteria was slight change of bacteria morphology. Membrane remained intact despite significant change of chemical content of membrane components.This is the peer reviewed version of the paper: Marković, Z. M., Matijašević, D. M., Pavlović, V. B., Jovanović, S. P., Holclajtner-Antunović, I. D., Špitalský, Z., Mičušik, M., Dramićanin, M. D., Milivojević, D. D., Nikšić, M. P., & Todorović Marković, B. M. (2017). Antibacterial potential of electrochemically exfoliated graphene sheets. Journal of Colloid and Interface Science, 500, 30–43. [https://doi.org/10.1016/j.jcis.2017.03.110][https://www.sciencedirect.com/science/article/abs/pii/S0021979717303776?via%3Dihub

Antibacterial polymer composites based on hydrophobic quantum dots for public transport applications

Invited lectur

Electrospinning tissue engineering and wound dressing scaffolds from polymer-titanium dioxide nanocomposites

Electrospinning is widely used to fabricate nanoscale fibers from natural and synthetic polymers. Electrospun fibers have potential application in tissue engineering as well as in the design of catalysts, batteries, electronic sensors, packages, filtration membranes, medical implants, wound dressings, and medical fabrics, and drug delivery systems. Fibers offer a porous structure with a high surface area to volume ratio, which is a highly desired property in various applications. Integrating other materials such as metals nanoparticles or ceramics in electrospun fibers is emerging as a route to new nanoscale composites materials with enhanced functional properties. Incorporating nanoparticles on or within the nanofibrous scaffold impart functional properties with implication for catalysis, optoelectronics, and biomedicine. Indeed, these electrospun polymer-nanoparticles composites are a new frontier in biomedicine, where their relevance to tissue engineering, wound dressing, drug delivery is emerging. Here, we summarise advances in electrospun tissue engineering and wound dressing platforms developed from polymer-titanium dioxide nanocomposites