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1.
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.

2.
Materials (Basel) ; 17(6)2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38541509

RESUMO

The paper presents the new eco-friendly method of bleaching process of the cellulose fibre materials. Cellulose materials were bleached using hydrogen peroxide (both in aqueous solution, vapours, ozone and by the combined action of gaseous hydrogen peroxide and ozone. The method using hydrogen peroxide in aqueous solution presents the standard procedure and was used as the comparison technique. The bleaching processes using gaseous oxidants were carried out in a prototype device for dry, low-temperature treatment of fibrous materials with the use of oxidising agents in the gas phase. The influence of the innovative gas-phase bleaching method on the cotton samples' properties was analysed by Scanning Electron Microscopy (SEM), evaluation of the colour and whiteness, assessment of the polymerisation degree (DP), analysis of the mechanical properties and sorption capacity as well as microbiological assessment against colonies of Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) bacteria. The comparison of the obtained results led to the conclusion that the bleaching processes using gas-phase agents-vaporised hydrogen peroxide, ozone or their combination-are non-invasive. The applied bleaching processes resulted in a slightly lower whiteness parameters than standard bath bleaching. After the bleaching processes with ozone and vaporised hydrogen peroxide separately, the decrease in the DP and tensile strength was similar to that observed after the bleaching with aqueous H2O2. When both processes were used together, a higher reduction in DP and tensile strength was noticed. Both oxidising agents showed a strong biocidal effect against bacteria. Gas-phase bleaching procedures, due to the lower temperature (35 °C vs. 98 °C) and minimal water consumption, have economic and environmental advantages, which allows their use in semi-industrial applications. It has been shown that the treatment of cotton fabrics using ozone and hydrogen peroxide in the gas phase allows to simultaneously obtain the bleaching and disinfection effect.

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.
Materials (Basel) ; 16(16)2023 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-37629939

RESUMO

Literature reviews have described the applications of silver, copper, and zinc ions and metallic particles of Cu, Ti, and Zn oxides, which have been found to be useful antimicrobial reagents for the biofunctionalization of various materials and their surfaces. For this purpose, compositions of water dispersions containing emulsions of synthetic copolymers based on acrylic and vinyl monomers, polysaccharides (hydroxyethyl cellulose and starch), and various additives with wetting and stabilizing properties were used. Many stable water dispersions of different chemical compositions containing bioactive chemical compounds (copper silicate hydrate, titanium dioxide, and zinc oxide (and other auxiliary substances)) were developed. They were used for the preparation of thin hybrid coatings having good antimicrobial properties against Gram-negative bacteria (Escherichia coli), Gram-positive bacteria (Staphylococcus aureus), and yeast fungus (Candida albicans). Polyester (PES) and polylactide (PLA) nonwovens were modified using the dip-coating method, while PES and cotton fabrics were biofunctionalized by means of dip-coating and coating methods. The antimicrobial (antibacterial and antifungal) properties of the textile materials (nonwovens and fabrics) biofunctionalized with the above-mentioned bioactive agents exhibiting antimicrobial properties (CuSiO3, TiO2, ZnO, or ZnO∙SiO2) were strongly dependent on the agents' content in the water dispersions. The PES and PLA nonwovens, modified on the surface with water compositions containing copper silicate hydrate, showed good antibacterial properties against the Gram-negative bacteria Escherichia coli, even at a content of 1 wt.% CuSiO3∙xH2O, and against the Gram-positive bacteria Staphylococcus aureus, at the content of at least 5 wt.% CuSiO3∙xH2O. The bacterial growth reduction factor (R) was greater than 99% for most of the samples tested. Good antifungal properties against the fungus Candida albicans were found for the PES and PLA nonwoven fabrics modified with dispersions containing 5-7 wt.% CuSiO3∙xH2O and 4.2-5.0 wt.% TiO2. The addition of TiO2 led to a significant improvement in the antifungal properties of the PES and PLA nonwovens modified in this way. For the samples of PES WIFP-270 and FS F-5 nonwovens, modified with water dispersions containing 5.0 wt.% CuSiO3∙xH2O and 4.2-5.0 wt.% TiO2, the growth reduction factor for the fungus Candida albicans (R) reached values in the range of 80.9-98.0%. These new biofunctionalized polymeric nonwoven textile materials can find practical applications in the manufacture of filters for hospital air-conditioning systems and for the automotive industry, as well as in air purification devices. Moreover, similar antimicrobial modification of fabrics with the dip-coating or coating methods can be applied, for example, in the fabrication of fungi- and mold-resistant garden furniture.

5.
Materials (Basel) ; 17(1)2023 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-38204025

RESUMO

Plastics have recently become an indispensable part of everyone's daily life due to their versatility, durability, light weight, and low production costs. The increasing production and use of plastics poses great environmental problems due to their incomplete utilization, a very long period of biodegradation, and a negative impact on living organisms. Decomposing plastics lead to the formation of microplastics, which accumulate in the environment and living organisms, becoming part of the food chain. The contamination of soils and water with poly(vinyl chloride) (PVC) seriously threatens ecosystems around the world. Their durability and low weight make microplastic particles easily transported through water or air, ending up in the soil. Thus, the problem of microplastic pollution affects the entire ecosystem. Since microplastics are commonly found in both drinking and bottled water, humans are also exposed to their harmful effects. Because of existing risks associated with the PVC microplastic contamination of the ecosystem, intensive research is underway to develop methods to clean and remove it from the environment. The pollution of the environment with plastic, and especially microplastic, results in the reduction of both water and soil resources used for agricultural and utility purposes. This review provides an overview of PVC's environmental impact and its disposal options.

6.
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.

7.
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.

8.
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
9.
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.

10.
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.

11.
Molecules ; 23(4)2018 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-29642559

RESUMO

The alkaline deacylation of a representative series of 1-(acylamino)alkylphosphonic acids [(AC)-AAP: (AC) = Ac, TFA, Bz; AAP = GlyP, AlaP, ValP, PglP and PheP] in an aqueous solution of KOH (2M) was investigated. The results suggested a two-stage reaction mechanism with a quick interaction of the hydroxyl ion on the carbonyl function of the amide R-C(O)-N(H)- group in the first stage, which leads to instant formation of the intermediary acyl-hydroxyl adducts of R-C(O-)2-N(H)-, visible in the 31P NMR spectra. In the second stage, these intermediates decompose slowly by splitting of the RC(O-)2-N(H)- function with the subsequent formation of 1-aminoalkylphosphonate and carboxylate ions.


Assuntos
Aminoácidos/química , Organofosfonatos/química , Acilação , Hidróxidos/química , Espectroscopia de Ressonância Magnética/métodos , Modelos Moleculares , Estrutura Molecular , Termodinâmica , Água/química
12.
Chirality ; 30(2): 131-140, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29272065

RESUMO

The first successful enantioseparation of representative O,O-diphenyl-N-arylthioureidoalkylphosphonates, (±)-Ptc-ValP (OPh)2 & (±)-Ptc-LeuP (OPh)2 and thiourylenedi(isobutyl phosphonate), Tcm[ValP (OPh)2 ]2 on analytical and semipreparative scale was achieved by high-performance liquid chromatography using polysaccharide-based chiral stationary phases (CPs). Atc-AAP (OPh)2 was obtained using modified tricomponent condensations of the corresponding aldehydes, N-arylthiourea and triphenyl phosphite whereas Tcm[ValP (OPh)2 ]2 by the condensations of aldehydes, thiourea, and triphenyl phosphite. The prepared, racemic (±)-Atc-AAP (OPh)2 [(±)-Ptc-ValP (OPh)2 , (±)-Ptc-LeuP (OPh)2 , (±)-Ptc-PglyP (OPh)2 and (±)-Ntc-PglyP (OPh)2 ] and racemic (±)-Tcm[AAP (OPh)2 ]2 [(±)-Tcm[NvaP (OPh)2 ]2 & (±)-Tcm[ValP (OPh)2 ]2 ] were adequately characterized and used for chromatographic separations on high-performance liquid chromatography-chiral stationary phases. The best results were obtained for (±)-Ptc-ValP (OPh)2 , (±)-Ptc-LeuP (OPh)2 and (±)-Tcm[ValP (OPh)2 ]2 .

13.
Dalton Trans ; 45(5): 2308-17, 2016 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-26631424

RESUMO

The reactions of 1-aminoalkylphosphonic acids with bromine-water, chlorine-water and iodine-water were investigated. The formation of phosphoric(v) acid, as a result of a halogen-promoted cleavage of the Cα-P bond, accompanied by nitrogen release, was observed. The dephosphonylation of 1-aminoalkylphosphonic acids was found to occur quantitatively. In the reactions of 1-aminoalkylphosphonic acids with other halogen-water reagents investigated by (31)P NMR, scission of the Cα-P bond was also observed, the reaction rates being comparable for bromine and chlorine, but much slower for iodine.

14.
Acta Biochim Pol ; 62(1): 139-50, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25730210

RESUMO

The approach for the unification of published proposals for the nomenclature and abbreviations of aminoalkylphosphonic acids and their derivatives is presented. Their modification was made on the basis of the IUPAC-IUB rules concerning the nomenclature and code system of proteinogenic amino acids. Our present proposal formulates the supplementary code and nomenclature system allowing unambiguous description of phosphonic analogs of proteinogenic amino acids, their analogs, homologs, metabolites, and derivatives including phosphonopeptides.


Assuntos
Ácidos Fosforosos/química , Terminologia como Assunto
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