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1.
Mater Sci Eng C Mater Biol Appl ; 100: 608-615, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30948097

RESUMO

A series of Zn-doped hybrid materials based on silica from tetraethoxysilane (TEOS) and hydroxypropyl cellulose (HPC) were prepared by a sol-gel route. The structure, morphology and thermal behavior of synthesized hybrids were characterized by infrared (IR) spectroscopy, ultraviolet-visible spectroscopy (UV-Vis), transmission electron microscopy (TEM) and differential thermal analysis with thermogravimetric analysis (DTA/TG). The obtained materials were investigated for a potential biomedical application. The antibacterial properties of hybrids were investigated by measuring the inhibition zones formed around the materials containing different zinc content in presence of reference strains of Gram-positive and Gram-negative bacteria. The biocompatibility tests showed no cytotoxicity and genotoxicity, as well as no changes in actin cytoskeleton organization for hybrids with Zn content below 5 wt%.


Assuntos
Tecnologia Biomédica/métodos , Celulose/análogos & derivados , Nanopartículas/química , Dióxido de Silício/química , Zinco/química , Citoesqueleto de Actina/efeitos dos fármacos , Citoesqueleto de Actina/metabolismo , Animais , Antibacterianos/farmacologia , Bacillus subtilis/efeitos dos fármacos , Bacillus subtilis/crescimento & desenvolvimento , Morte Celular/efeitos dos fármacos , Divisão Celular , Linhagem Celular , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Celulose/química , Análise Diferencial Térmica , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Fibroblastos/citologia , Camundongos , Testes de Sensibilidade Microbiana , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta
2.
Carbohydr Polym ; 101: 1166-75, 2014 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-24299888

RESUMO

Amorphous hybrids based on sodium salt of carboxymethyl cellulose (CMC) and tetraethoxysilane (TEOS) containing silver nanoparticles were prepared by sol-gel method. The amorphous structure, morphology and antibacterial behavior were clarified. The thermal stability of obtained hybrids decreased with the increase in silver content from 0.5 to 1.5 wt%. Infrared spectra of the material suggest that the main interaction between the cellulose ether and silica network is via hydrogen bonds (bands at approximately 3,540 and 3,625 cm(-1)). According to UV-vis spectra the silver is present in two different states Ag(+) (absorption band at approximately 210 nm) and Ag(0) (band at approximately 300 nm). The different sizes of silver particles are present as clusters. It was demonstrated that these hybrids have a well pronounced antibacterial activity against B. subtilis and E. coli K12. Even the hybrid with 0.5 wt% Ag has efficient antibacterial activity for both Gram-positive and Gram-negative bacteria.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Carboximetilcelulose Sódica/química , Carboximetilcelulose Sódica/farmacologia , Dióxido de Silício/química , Prata/química , Bacillus subtilis/efeitos dos fármacos , Escherichia coli K12/efeitos dos fármacos , Nanopartículas Metálicas/química , Silanos/química
3.
Biotechnol Biotechnol Equip ; 28(4): 747-752, 2014 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-26740774

RESUMO

Antibacterial SiO2 hybrid materials based on tetraethyl orthosilicate (TEOS), hydroxypropylmethylcellulose (HPMC) and silver were prepared by the sol-gel method. The content of cellulose derivate was 5 wt% and the silver concentration varied from 0.5 wt% to 2.5 wt%. The amorphous nature, morphology and antibacterial behaviour were studied. Fourier transform infrared (FTIR) spectra of the hybrids showed characteristic peaks for SiO2 network. Scanning electron microscope (SEM) analysis confirmed the formation of spherically shaped silver nanoparticles with a size of 30 nm on the matrix surfaces. Bacillus subtilis and Escherichia coli K12 were used as model microorganisms. The hybrid materials demonstrated bacteriostatic and bactericidal effect on the tested bacteria. Highest sensitivity to the obtained hybrids was observed in B. subtilis with significant lag-phase delay and biggest inhibition zone sizes.

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