Effect of the size of silica nanoparticles on wettability and surface chemistry of sol–gel superhydrophobic and oleophobic nanocomposite coatings

TiO2 is widely used in biomaterial implants. The topography, chemical and structural properties of titania surfaces are an important aspect to study. The size of TiO2 nanoparticles synthetized by sol–gel method can influence the responses in the biological environment, and by using appropriate heat treatments different contents of different polymorphs can be formed. Protein adsorption is a crucial step for the biological responses, involving, in particular, albumin, the most abundant blood protein. In this theoretical work, using molecular mechanics and molecular dynamics methods, the adsorption process of an albumin subdomain is reported both onto specific different crystallographic faces of TiO2 anatase and also on its ideal three-dimensional nanosized crystal, using the simulation protocol proposed in my previous theoretical studies about the adsorption process on hydrophobic ordered graphene-like or hydrophilic amorphous polymeric surfaces. The different surface chemistry of anatase crystalline faces and the nanocrystal topography influence the adsorption process, in particular the interaction strength and protein fragment conformation, then its biological activity. This theoretical study can be a useful tool to better understand how the surface chemistry, crystal structure, size and topography play a key role in protein adsorption process onto anatase surface so widely used as biomaterial.

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Development of Novel Oral Formulations of Disulfide Antioxidants Based on Porous Silica for Controlled Release of the Drugs

Materials ◽

10.3390/ma14040963 ◽

2021 ◽

Vol 14 (4) ◽

pp. 963

Author(s):

Ekaterina S. Dolinina ◽

Elena V. Parfenyuk

Keyword(s):

Antioxidant Activity ◽

Surface Chemistry ◽

Sol Gel ◽

Porous Silica ◽

The Body ◽

Oral Drug ◽

Therapeutic Concentration ◽

Release Process ◽

Zero Order Kinetics ◽

Long Time

Powerful antioxidant α-lipoic acid (LA) exhibits limited therapeutic efficiency due to its pharmacokinetic properties. Therefore, the purpose of this work was to evaluate the ability of silica-based composites of LA as well as its amide (lipoamide, LM), as new oral drug formulations, to control their release and maintain their therapeutic concentration and antioxidant activity in the body over a long time. The composites synthesized at different sol–gel synthesis pH and based on silica matrixes with various surface chemistry were investigated. The release behavior of the composites in media mimicking pH of digestive fluids (pH 1.6, 6.8, and 7.4) was revealed. The effects of chemical structure of the antioxidants, synthesis pH, surface chemistry of the silica matrixes in the composites as well as the pH of release medium on kinetic parameters of the drug release and mechanisms of the process were discussed. The comparative analysis of the obtained data allowed the determination of the most promising composites. Using these composites, modeling of the release process of the antioxidants in accordance with transit conditions of the drugs in stomach, proximal, and distal parts of small intestine and colon was carried out. The composites exhibited the release close to the zero order kinetics and maintained the therapeutic concentration of the drugs and antioxidant effect in all parts of the intestine for up to 24 h. The obtained results showed that encapsulation of LA and LM in the silica matrixes is a promising way to improve their bioavailability and antioxidant activity.

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pH Shock-promoted lysozyme corona for efficient pathogenic infections treatment: effects of surface chemistry of mesoporous silica nanoparticles and loading method

Enzyme and Microbial Technology ◽

10.1016/j.enzmictec.2021.109974 ◽

2021 ◽

pp. 109974

Author(s):

Parvaneh Esmaeilnejad-Ahranjani ◽

Ayyoob Arpanaei

Keyword(s):

Mesoporous Silica ◽

Surface Chemistry ◽

Silica Nanoparticles ◽

Treatment Effects ◽

Mesoporous Silica Nanoparticles ◽

Loading Method ◽

Ph Shock

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Selective porous gates made from colloidal silica nanoparticles

Beilstein Journal of Nanotechnology ◽

10.3762/bjnano.6.215 ◽

2015 ◽

Vol 6 ◽

pp. 2105-2112 ◽

Cited By ~ 9

Author(s):

Roberto Nisticò ◽

Paola Avetta ◽

Paola Calza ◽

Debora Fabbri ◽

Giuliana Magnacca ◽

...

Keyword(s):

Silica Nanoparticles ◽

Spin Coating ◽

Colloidal Silica ◽

Sol Gel ◽

Chemical Species ◽

Solvent System ◽

Porous Films ◽

Nanoporous Films ◽

Poly Ethylene Oxide ◽

Poly Ethylene

Highly selective porous films were prepared by spin-coating deposition of colloidal silica nanoparticles on an appropriate macroporous substrate. Silica nanoparticles very homogenous in size were obtained by sol–gel reaction of a metal oxide silica precursor, tetraethyl orthosilicate (TEOS), and using polystyrene-block-poly(ethylene oxide) (PS-b-PEO) copolymers as soft-templating agents. Nanoparticles synthesis was carried out in a mixed solvent system. After spin-coating onto a macroporous silicon nitride support, silica nanoparticles were calcined under controlled conditions. An organized nanoporous layer was obtained characterized by a depth filter-like structure with internal porosity due to interparticle voids. Permeability and size-selectivity were studied by monitoring the diffusion of probe molecules under standard conditions and under the application of an external stimulus (i.e., electric field). Promising results were obtained, suggesting possible applications of these nanoporous films as selective gates for controlled transport of chemical species in solution.

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Natural Rubber Reinforced with Silica Nanoparticles Extracted from Jasmine and Riceberry Rice Husk Ashes

Materials Science Forum ◽

10.4028/www.scientific.net/msf.936.31 ◽

2018 ◽

Vol 936 ◽

pp. 31-36 ◽

Cited By ~ 2

Author(s):

Wichudaporn Seangyen ◽

Paweena Prapainainar ◽

Pongdhorn Sae-Oui ◽

Surapich Loykulnant ◽

Peerapan Dittanet

Keyword(s):

Tensile Strength ◽

Natural Rubber ◽

Silica Nanoparticles ◽

Rice Husk ◽

Sol Gel ◽

Rubber Matrix ◽

Reinforcing Fillers ◽

Rubber Nanocomposites ◽

Jasmine Rice ◽

20 Nm

Silica nanoparticles were synthesized by rice husk ash (RHA) produced from jasmine rice husk and riceberry rice husk via sol-gel method for the use as reinforcing fillers in natural rubber (NR). The obtained silica nanoparticles are spherical in shape and the particle sizes were observed to be in the 10-20 nm range with uniformly size distribution. The surface of silica nanoparticles was treated with a silane coupling agent confirmed by FTIR. The treated silica nanoparticles were then incorporated into NR and vulcanized with electron beam irradiation. The rubber nanocomposites with silica nanoparticles, produced from jasmine rice husk and riceberry rice husk, resulted in higher mechanical properties (tensile strength and modulus) than neat rubber vulcanizate. The modified rubber vulcanizates revealed rougher surface with tear lines as compared to the neat rubber vulcanizates, indicating the improved strength. Interestingly, the rubber nanocomposites with silica nanoparticles from jasmine rice husk showed higher tensile strength and modulus than silica nanoparticles produced from riceberry rice husk. The micrographs indicated better dispersion of NR composites with jasmine rice husk which leads to a strong interaction between silica nanoparticles and rubber matrix, thereby improving the strength.

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