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1.
Materials (Basel) ; 17(9)2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38730835

RESUMO

Biological wastewater treatment using trickle bed reactors is a commonly known and used solution. One of the key elements of the proper operation of the trickle bed bioreactor is the appropriate selection of biofilm support elements. The respective properties of the bioreactor packing media used can influence, among other things, the efficiency of the treatment process. In this study, the possibility of polyester waste material usage for the preparation of the biofilm support elements was tested. The following properties were checked: adsorption capacity, swelling, surface morphology, microbicidal properties, as well as the possibility of their use in biological wastewater treatment. The tested elements did not adsorb copper nor showed microbicidal properties for bacterial strains Escherichia coli and Staphylococcus aureus as well as fungal strains Aspergillus niger and Chaetomium globosum. The hydrophilic and rough nature of the element surface was found to provide a friendly support for biofilm formation. The durability of the elements before and after their application in the biological treatment process was confirmed by performing tests such as compressive strength, FTIR analysis, hardness analysis and specific surface area measurement. The research confirmed the applicability of the packing elements based on polyester textile waste to the treatment of textile wastewater. The treatment efficiency of the model wastewater stream was above 90%, while in the case of a stream containing 60% actual industrial wastewater it was above 80%. The proposed solution enables the simultaneous management of textile waste and wastewater treatment, which is consistent with the principles of a circular economy. The selected waste raw material is a cheap and easily available material, and the use of the developed packing elements will reduce the amount of polyester materials ending up in landfills.

2.
Materials (Basel) ; 17(3)2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38591465

RESUMO

The paper presents the investigation of the biological properties of Poly(Lactide)-Copper composite material obtained by sputter deposition of copper onto Poly(lactide) melt-blown nonwoven fabrics. The functionalized composite material was subjected to microbial activity tests against colonies of Gram-positive (Staphylococcus aureus), Gram-negative (Escherichia coli, Pseudomonas aeruginosa) bacteria, Chaetomium globosum and Candida albicans fungal mold species and biochemical-hematological tests including the evaluation of the Activated Partial Thromboplastin Time, Prothrombin Time, Thrombin Time and electron microscopy fibrin network imaging. The substantial antimicrobial and antifungal activities of the Poly(Lactide)-Copper composite suggests potential applications as an antibacterial/antifungal material. The unmodified Poly(Lactide) fabric showed accelerated human blood plasma clotting in the intrinsic pathway, while copper plating abolished this effect. Unmodified PLA itself could be used for the preparation of wound dressing materials, accelerating coagulation in the case of hemorrhages, and its modifications with the use of various metals might be applied as new customized materials where blood coagulation process could be well controlled, yielding additional anti-pathogen effects.

3.
Mar Drugs ; 21(12)2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-38132946

RESUMO

Alginate-based materials have gained significant attention in the medical industry due to their biochemical properties. In this article, we aimed to synthesize Cotton-Alginate-Copper Composite Materials (COT-Alg(-)Cu(2+)). The main purpose of this study was to assess the biochemical properties of new composites in the area of blood plasma coagulation processes, including activated partial thromboplastin time (aPTT), prothrombin time (PT), and thrombin time (TT). This study also involved in vitro antimicrobial activity evaluation of materials against representative colonies of Gram-positive and Gram-negative bacteria and antifungal susceptibility tests. The materials were prepared by immersing cotton fibers in an aqueous solution of sodium alginate, followed by ionic cross-linking of alginate chains within the fibers with Cu(II) ions to yield antimicrobial activity. The results showed that the obtained cotton-alginate-copper composites were promising materials to be used in biomedical applications, e.g., wound dressing.


Assuntos
Alginatos , Cobre , Cobre/química , Alginatos/química , Antibacterianos/farmacologia , Antibacterianos/química , Bactérias Gram-Negativas , Bactérias Gram-Positivas , Coagulação Sanguínea , Tempo de Protrombina , Tempo de Tromboplastina Parcial , Íons/farmacologia
4.
Antibiotics (Basel) ; 10(11)2021 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-34827265

RESUMO

The aim of this study was to investigate an antimicrobial and degradable composite material consisting of melt-blown poly(lactic acid) nonwoven fabrics, alginate, and zinc. This paper describes the method of preparation and the characterization of the physicochemical and antimicrobial properties of the new fibrous composite material. The procedure consists of fabrication of nonwoven fabric and two steps of dip-coating modification: (1) impregnation of nonwoven samples in the solution of alginic sodium salt and (2) immersion in a solution of zinc (II) chloride. The characterization and analysis of new material included scanning electron microscopy (SEM), specific surface area (SSA), and total/average pore volume (BET). The polylactide/alginate/Zn fibrous composite were subjected to microbial activity tests against colonies of Gram-positive (Staphylococcus aureus), Gram-negative (Escherichia coli) bacterial strains, and the following fungal strains: Aspergillus niger van Tieghem and Chaetomium globosum. These results lay a technical foundation for the development and potential application of new composite as an antibacterial/antifungal material in biomedical areas.

5.
Antibiotics (Basel) ; 10(2)2021 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-33669752

RESUMO

This research is focused on a synthesis of copper-cellulose phosphates antimicrobial complexes. Vapor-phase phosphorylations of cellulose were achieved by exposing microcrystalline cellulose to phosphorus trichloride (PCl3) vapors. The cellulose-O-dichlorophosphines (Cell-O-PCl2) formed were hydrolyzed to cellulose-O-hydrogenphosphate (P(III)) (Cell-O-P(O)(H)(OH)), which, in turn, were converted into corresponding copper(II) complexes (Cell-O-P(O)(H)(OH)∙Cu2+). The analysis of the complexes Cell-O-P(O)(H)(OH)∙Cu2+ covered: scanning electron microscopy (SEM), attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), atomic absorption spectrometry with flame excitation (FAAS), and bioactivity tests against representative Gram-negative bacteria (Escherichia coli) and Gram-positive bacteria (Staphylococcus aureus). The antimicrobial tests of synthesized Cell-O-P(O)(H)(OH)∙Cu2+ revealed their potential applications as an antibacterial material.

6.
Mar Drugs ; 18(12)2020 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-33371380

RESUMO

In recent years, due to an expansion of antibiotic-resistant microorganisms, there has been growing interest in biodegradable and antibacterial polymers that can be used in selected biomedical applications. The present work describes the synthesis of antimicrobial polylactide-copper alginate (PLA-ALG-Cu2+) composite fibers and their characterization. The composites were prepared by immersing PLA fibers in aqueous solution of sodium alginate, followed by ionic cross-linking of alginate chains within the polylactide fibers with Cu(II) ions to yield PLA-ALG-Cu2+ composite fibers. The composites, so prepared, were characterized by scanning electron microscopy (SEM), UV/VIS transmittance and attenuated total reflection Fourier-transform infrared spectroscopy ATR-FTIR, and by determination of their specific surface area (SSA), total/average pore volumes (through application of the 5-point Brunauer-Emmett-Teller method (BET)), and ability to block UV radiation (determination of the ultraviolet protection factor (UPF) of samples). The composites were also subjected to in vitro antimicrobial activity evaluation tests against colonies of Gram-negative (E. coli) and Gram-positive (S. aureus) bacteria and antifungal susceptibility tests against Aspergillus niger and Chaetomium globosum fungal mold species. All the results obtained in this work showed that the obtained composites were promising materials to be used as an antimicrobial wound dressing.


Assuntos
Alginatos/química , Alginatos/farmacologia , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Poliésteres/química , Poliésteres/farmacologia , Alginatos/análise , Anti-Infecciosos/análise , Aspergillus niger/efeitos dos fármacos , Aspergillus niger/fisiologia , Avaliação Pré-Clínica de Medicamentos/métodos , Escherichia coli/efeitos dos fármacos , Escherichia coli/fisiologia , Testes de Sensibilidade Microbiana/métodos , Microscopia Eletrônica de Varredura/métodos , Poliésteres/análise , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/fisiologia
7.
Materials (Basel) ; 13(18)2020 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-32911707

RESUMO

The paper presents the method of synthesis; physico-technical and biological characterization of a new composite material (PLA-Cu0) obtained by sputter deposition of copper on melt-blown poly(lactide) (PLA) non-woven fabrics. The analysis of these biofunctionalized non-woven fabrics included: ultraviolet/visible (UV/VIS) transmittance; scanning electron microscopy/energy-dispersive spectroscopy (SEM/EDS); attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy; ability to block UV radiation; filtration parameters (air permeability); and tensile testing. The functionalized non-woven composite materials were subjected to antimicrobial tests against colonies of Gram-negative (Escherichia coli), Gram-positive (Staphylococcus aureus) bacteria and antifungal tests against the Chaetomium globosum fungal mould species. The antibacterial and antifungal activity of PLA-Cu0 suggests potential applications as an antimicrobial material.

8.
Polymers (Basel) ; 12(4)2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32244602

RESUMO

This research is focused on obtaining antimicrobial hybrid materials consisting of poly(lactide) nonwoven fabrics and using phosphoro-organic compound-fosfomycin-as a coating and modifying agent. Polylactide (PLA) presents biodegradable polymer with multifunctional application, widely engaged in medical related areas. Fosfomycin as functionalized phosphonates presents antibiotic properties expressed by broad spectrum of antimicrobial properties. The analysis of these biofunctionalized nonwoven fabrics processed by the melt-blown technique, included: scanning electron microscopy (SEM), UV/VIS transmittance, FTIR spectrometry, air permeability. The functionalized nonwovens were tested on microbial activity tests against colonies of gram-positive (Staphylococcus aureus) and gram-negative(Escherichia coli) bacteria.

9.
Chemosphere ; 75(2): 250-5, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19155044

RESUMO

The anaerobic biological azo dyes reduction process was successfully applied to decolourization of the concentrates from the nanofiltration treatment of real textile effluents. The anaerobic phase was followed by aerobic oxidation aimed at the destruction of the aromatic amine released from azo dye. In the first experiment sequential batch reactor (SBR) combining both the anaerobic and aerobic phase in one unit was used. In the second one the anaerobic stage was separated from the aerobic one. The anaerobic phase fulfilled its aim (decolourization) in both systems (over 90%). In opposite, the aromatic amine was completely degraded in the aerobic reactor (two-sludge system), whereas the orthanilic acid was not degraded (during the aerobic phase) in SBR reactor. The COD reduction was also higher in the two-sludge system than in SBR.


Assuntos
Corantes/metabolismo , Filtração/métodos , Têxteis , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/metabolismo , Purificação da Água/métodos , Aerobiose , Anaerobiose , Biodegradação Ambiental , Reatores Biológicos , Corantes/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação
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