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1.
Polymers (Basel) ; 15(13)2023 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-37447477

RESUMO

A silver-containing gel based on polyvinyl alcohol and aryloxycyclotriphosphazene containing ß-carboxyethenylphenoxy and p-formylphenoxy groups has been developed. Phosphazene was synthesized via the Doebner reaction from hexakis[(4-formyl)phenoxy]cyclotriphosphazene and malonic acid and characterized by 1H, 13C, and 31P NMR spectroscopy and MALDI-TOF mass spectrometry. The study of the gel using scanning electron microscopy showed that the gel contains open pores and can absorb wound exudate. The maximum water absorption capacity of the gel was 272%, which was reached after 80 min of testing. The antimicrobial activity of the obtained silver-containing gel was evaluated using the diffusion method. The gel was found to inhibit the growth of the main microorganisms in contact with the skin: the bacteria S. aureus, P. aeruginosa, E. coli, B. subtilis, S. epidermidis, and C. stationis and the fungus C. albicans. The study of the wound-healing effect of the gel in vivo showed a decrease in the wound area of the rabbit hind limb by 91.43% (p < 0.05) on the 10th day of observation and a decrease in the content of C-reactive protein in the rabbit blood serum by 1.3 times (p < 0.05).

2.
Polymers (Basel) ; 14(5)2022 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-35267686

RESUMO

This review aims to describe and critically analyze studies published over the past four years on the application of polymeric dental nanomaterials as antimicrobial materials in various fields of dentistry. Nanoparticles are promising antimicrobial additives to restoration materials. According to published data, composites based on silver nanoparticles, zinc(II), titanium(IV), magnesium(II), and copper(II) oxide nanoparticles, chitosan nanoparticles, calcium phosphate or fluoride nanoparticles, and nanodiamonds can be used in dental therapy and endodontics. Composites with nanoparticles of hydroxyapatite and bioactive glass proved to be of low efficiency for application in these fields. The materials applicable in orthodontics include nanodiamonds, silver nanoparticles, titanium(IV) and zinc(II) oxide nanoparticles, bioactive glass, and yttrium(III) fluoride nanoparticles. Composites of silver nanoparticles and zinc(II) oxide nanoparticles are used in periodontics, and nanodiamonds and silver, chitosan, and titanium(IV) oxide nanoparticles are employed in dental implantology and dental prosthetics. Composites based on titanium(IV) oxide can also be utilized in maxillofacial surgery to manufacture prostheses. Composites with copper(II) oxide nanoparticles and halloysite nanotubes are promising materials in the field of denture prosthetics. Composites with calcium(II) fluoride or phosphate nanoparticles can be used in therapeutic dentistry for tooth restoration.

3.
Acta Crystallogr E Crystallogr Commun ; 77(Pt 2): 134-137, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33614141

RESUMO

The asymmetric unit of the title compound, sodium 2-[1-methyl-5-(4-methyl-benzo-yl)-1H-pyrrol-2-yl]acetate dihydrate, Na+·C15H14NO3 -·2H2O, contains two sodium cations, two organic anions (A and B) and two water mol-ecules. The coordination geometry around the sodium cations corresponds to a distorted octa-hedron. Each pair of sodium cations (A-A or B-B) is chelated by two bridging anions coordinated by the O atoms of the deprotonated carb-oxy-lic groups, and each sodium atom is coordinated by an O atom of a third anion, which connects pairs of sodium atoms, and a water mol-ecule. As a result, a two-dimensional polymer is formed in the crystal. Hirshfeld surface analysis and two-dimensional fingerprint plots were used to analyze the inter-molecular contacts present in the crystal.

4.
Acta Crystallogr E Crystallogr Commun ; 76(Pt 9): 1407-1411, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32939290

RESUMO

The chiral title compound, C16H20N2O2, which can be used for producing active pharmaceutical ingredients for treatment of type 2 pancreatic diabetes and other pathologies dependent on insulin resistance, was prepared from (1R,3S)-camphoric acid and o-phenyl-enedi-amine. It crystallized from an ethanol solution in the chiral monoclinic P21 space group. The five-membered ring adopts a twisted conformation with the methyl-substituted C atoms displaced by -0.273 (5) and 0.407 (5) Šfrom the mean plane through the other three atoms. In the crystal, mol-ecules are linked by O-H⋯N hydrogen bonds, forming chains along the a-axis direction. Hirshfeld surface analysis and two-dimensional fingerprint plots were used to analyze the inter-molecular contacts present in the crystal.

5.
Polymers (Basel) ; 12(5)2020 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-32443901

RESUMO

A modifier consisting of the mixture of cyclotriphosphazenes containing 4-allyl-2-methoxyphenoxy and ß-carboxyethenylphenoxy moieties was developed for administration with acrylate dental restorative compositions. The synthesized compounds were characterized by 1H and 13C NMR spectroscopy and MALDI-TOF mass spectrometry. The optimal conditions to combine the modifier with the starting dental mixture consisting of bis-GMA and TGM-3 were revealed by differential scanning calorimetry (DSC) method. Properties of the cured modified compositions were evaluated for the compliance with requirements of ISO 4049:2019. It was found that these compositions possess the increased adhesion to dental tissues and cure depth and the decreased water sorption and water solubility. The values of elastic modules, destructive compressive stress and microhardness were also increasing along with the increased content of the modifier in the composition.

6.
Polymers (Basel) ; 11(7)2019 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-31319452

RESUMO

The method of optical wedge revealed that the optimum temperature for compatibility of hexakis(4-acetamidophenoxy)cyclotriphosphazene (ACP) and DER-331 epoxy resin is in the range of 220-260 °C. The interdiffusion time of components at these temperatures is about 30 min. The TGA and differential scanning calorimetry (DSC) methods revealed the curing temperature of 280 °Ð¡ for this composition. IR spectroscopy confirmed that the reaction between the resin and ACP is completed within 10 min. According to the DSC data, a glass transition temperature of 130 °Ð¡ was estimated for the cured resin. Combustion test UL-94 demonstrated that the obtained material can be assigned to the fireproof category of V-0. Burning droplets were not formed during the burning. The coke formed during the combustion of samples possessed a dense and porous structure. The shape of pores is closed, while their size is in the range of 0.2-200 µm.

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