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1.
Ultrason Sonochem ; 68: 105198, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32593966

RESUMO

Nowadays celiac disease is becoming more common. It is the autonomic genetic disease that is accompanied by damage to the intestines due to a reaction to eating some proteins. People who are suffering from celiac disease cannot eat food containing gluten, including dough made from gluten-containing seeds. But the gluten-free dough has commonly bad rheological properties and cannot be used for automatic molding the dumplings. In this article, we propose the ultrasonic-assisted technology to fabricate the gluten-free dough with improved rheological properties acceptable for automatic molding of the dumplings. Application of ultrasonic treatment at a frequency of 35 kHz during the dough preparation leads to the homogenization of the dough structure and changing the rheological properties of the dough. The ultrasound induces mechanical, physical and chemical/biochemical changes of the dough components through cavitation. The sonication causes a doubled dough volume increase followed by an additional mass yield of the dumplings equal 2-10% per kilogram of dough. Besides extra beneficial economic effect, our technology provides an additional sterilization effect of the fabricated dough.

2.
Mater Sci Eng C Mater Biol Appl ; 109: 110458, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32228946

RESUMO

Different metal particles are increasingly used to target bacteria as an alternative to antibiotics. Despite numerous data about treating bacterial infections, the utilization of metal particles in antibacterial coatings for implantable devices and medicinal materials promoting wound healing. The antibacterial mechanisms of nanoscale and microscale particles are poorly understood, but the currently accepted mechanisms include oxidative stress induction, metal ion release, and non-oxidative mechanisms. Thus, investigation of the antibacterial mechanisms of nanostructured metal particles is very important for the development of more effective antimicrobial materials. However, it is very difficult to develop a proper model for revealing the antibacterial mechanisms due to difficulty to choose a method that allows obtaining materials of various properties under approximately the same conditions. In this paper, we propose a green and feasible technique to create critical conditions for modification of zinc particles at highly non-equilibrium states. We demonstrate that the sonication process can be useful for fabrication the materials with oscillating physical, chemical and antibacterial properties. We believe this method besides medical applications can be also used in natural science basic research as an experimental tool for modelling the physical and chemical processes. After the sonication, the zinc particles exhibit a different surface morphology and amount of leached Zn2+ ions compared to initial ones. It has been revealed that oscillations of the Zn2+ ions concentration lead to oscillation the antibacterial properties. Thus, the properties of the materials can be easily altered by adjusting the ultrasound energy dissipated via varying the sonication.

3.
J Mater Chem B ; 7(43): 6810-6821, 2019 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-31608920

RESUMO

Drug delivery systems based on the zeolitic imidazolate framework ZIF-8 have recently attracted viable research interest owing to their capability of decomposing in acidic media and thus performing targeted drug delivery. In vivo realization of this mechanism faces a challenge of relatively slow decomposition rates, even at elevated acidic conditions that are barely achievable in diseased tissues. In this study we propose to combine drug delivery nanocomposites with a semiconductor photocatalytic agent that would be capable of inducing a local pH gradient in response to external electromagnetic radiation. In order to test this principle, a model drug-releasing nanocomposite comprising photocatalytic titania nanotubes, ZIF-8, and the antitumor drug doxorubicin has been investigated. This system was demonstrated to release the drug in a quantity sufficient for effectively suppressing IMR-32 neuroblastoma cells that were used as a model diseased tissue. With locally applied UV irradiation, this result was achieved within 40 minutes, which is a relatively short time compared to the release duration in systems without photocatalyst, typically taking from several hours to several days.

4.
Ultrason Sonochem ; 52: 437-445, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30594519

RESUMO

The influence of surface nanotopography of sonochemically generated mesoporous titania coatings (TMS) on the adhesion, proliferation, and osteogenic differentiation of human mesenchymal stem cells (hMSCs) have been investigated in vitro for the first time. It has been revealed that adhesion and proliferation of hMSCs is higher on disordered TMS surfaces compared to smooth polished titania surface after five days of incubation. Surprisingly, the sonochemically generated disordered nanotopography induces the differentiation of hMSCs into osteogenic direction in the absence of osteogenic medium in 14 days of incubation. Thus sonochemical nanostructuring of titanium based implants stimulates the regenerative process of bone tissue.


Assuntos
Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Nanoestruturas/química , Próteses e Implantes , Titânio/química , Titânio/farmacologia , Ondas Ultrassônicas , Adesão Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Humanos , Teste de Materiais , Nanotecnologia , Osteogênese/efeitos dos fármacos , Propriedades de Superfície , Fatores de Tempo
5.
Bioconjug Chem ; 29(11): 3793-3799, 2018 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-30350577

RESUMO

The development of stimuli-responsive nanocontainers is an issue of utmost importance for many applications such as targeted drug delivery, regulation of the cell and tissue behavior, making bacteria have useful functions and here converting light. The present work shows a new contribution to the design of polyelectrolyte (PE) containers based on surface modified mesoporous titania particles with deposited Ag nanoparticles to achieve chemical light upconversion via biofilms. The PE shell allows slowing down the kinetics of a release of loaded l-arabinose and switching the bacteria luminescence in a certain time. The hybrid TiO2/Ag/PE containers activated at 980 nm (IR) illumination demonstrate 10 times faster release of l-arabinose as opposed to non-activated containers. Fast IR-released l-arabinose switch bacteria fluorescence which we monitor at 510 nm. The approach described herein can be used in many applications where the target and delayed switching and light upconversion are required.


Assuntos
Arabinose/administração & dosagem , Biofilmes , Escherichia coli/fisiologia , Nanoestruturas/química , Polieletrólitos/química , Prata/química , Titânio/química , Arabinose/metabolismo , Portadores de Fármacos/química , Fluorescência , Humanos , Luminescência , Nanopartículas Metálicas/química
6.
Ultrason Sonochem ; 36: 146-154, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28069194

RESUMO

Titanium has been widely used as biomaterial for various medical applications because of its mechanical strength and inertness. This on the other hand makes it difficult to structure it. Nanostructuring can improve its performance for advanced applications such as implantation and lab-on-chip systems. In this study we show that a titania nanofoam on titanium can be formed under high intensity ultrasound (HIUS) treatment in alkaline solution. The physicochemical properties and morphology of the titania nanofoam are investigated in order to find optimal preparation conditions for producing surfaces with high wettability for cell culture studies and drug delivery applications. AFM and contact angle measurements reveal, that surface roughness and wettability of the surfaces depend nonmonotonously on ultrasound intensity and duration of treatment, indicating a competition between HIUS induced roughening and smoothening mechanisms. We finally demonstrate that superhydrophilic bio-and cytocompatible surfaces can be fabricated with short time ultrasonic treatment.

7.
Angew Chem Int Ed Engl ; 55(42): 13001-13004, 2016 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-27439779

RESUMO

We introduce a simple concept of a light induced pH change, followed by high amplitude manipulation of the mechanical properties of an adjacent polymer film. Irradiation of a titania surface is known to cause water splitting, and this can be used to reduce the environmental pH to pH 4. The mechanical modulus of an adjacent pH sensitive polymer film can thus be changed by more than an order of magnitude. The changes can be localized, maintained for hours and repeated without material destruction.

8.
Macromol Biosci ; 16(10): 1422-1431, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27276439

RESUMO

Polyelectrolyte block copolymer micelles assembled thin film is switched in response to local photocatalytic reactions on titanium dioxide, resulting in a layer of variable height, stiffness in response to visible light irradiation. Preosteoblasts migrate toward stiffer side of the substrates.


Assuntos
Movimento Celular , Elasticidade , Membranas Artificiais , Micelas , Osteoblastos/metabolismo , Titânio/química , Animais , Linhagem Celular , Camundongos , Osteoblastos/citologia
9.
Langmuir ; 32(16): 4016-21, 2016 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-26991479

RESUMO

A new effective method of photocatalytic deposition of hydroxyapatite (HA) onto semiconductor substrates is proposed. A highly ordered nanotubular TiO2 (TNT) layer formed on titanium via its anodization is chosen as the photoactive substrate. The method is based on photodecomposition of the phosphate anion precursor, triethylphosphate (TEP), on the semiconductor surface with the following reaction of formed phosphate anions with calcium cations presented in the solution. HA can be deposited only on irradiated areas, providing the possibility of photoresist-free HA patterning. It is shown that HA deposition can be controlled via pH, light intensity, and duration of the process. Energy-dispersive X-ray spectroscopy profile analysis and glow discharge optical emission spectroscopy of HA-modified TNT prove that HA deposits over the entire TNT depth. High biocompatibility of the surfaces is proven by protein adsorption and pre-osteoblast cell growth.

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