Surface Chemistry, Crystal Structure, Size and Topography Role in the Albumin Adsorption Process on TiO2 Anatase Crystallographic Faces and Its 3D-Nanocrystal: A Molecular Dynamics Study

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.

Download Full-text

Adsorption of Mussel Protein on Polymer Antifouling Membranes: A Molecular Dynamics Study

Molecules ◽

10.3390/molecules26185660 ◽

2021 ◽

Vol 26 (18) ◽

pp. 5660

Author(s):

Fengfeng Gao

Keyword(s):

Molecular Dynamics ◽

Molecular Dynamics Simulation ◽

Protein Adsorption ◽

Adsorption Process ◽

Molecular Level ◽

Dynamics Simulation ◽

Antifouling Coatings ◽

The Future ◽

Marine Engineering

Biofouling is one of the most difficult problems in the field of marine engineering. In this work, molecular dynamics simulation was used to study the adsorption process of mussel protein on the surface of two antifouling films—hydrophilic film and hydrophobic film—trying to reveal the mechanism of protein adsorption and the antifouling mechanism of materials at the molecular level. The simulated conclusion is helpful to design and find new antifouling coatings for the experiments in the future.

Download Full-text

Gold nanoparticles: role of size and surface chemistry on blood protein adsorption

Journal of Nanoparticle Research ◽

10.1007/s11051-013-1694-2 ◽

2013 ◽

Vol 15 (6) ◽

Cited By ~ 18

Author(s):

F. Benetti ◽

M. Fedel ◽

L. Minati ◽

G. Speranza ◽

C. Migliaresi

Keyword(s):

Gold Nanoparticles ◽

Surface Chemistry ◽

Protein Adsorption ◽

Blood Protein

Download Full-text

TiO2Coating and UV Photofunctionalization Enhance Blood Coagulation on Zirconia Surfaces

BioMed Research International ◽

10.1155/2019/8078230 ◽

2019 ◽

Vol 2019 ◽

pp. 1-9 ◽

Cited By ~ 5

Author(s):

Khalil Shahramian ◽

Aous Abdulmajeed ◽

Ilkka Kangasniemi ◽

Eva Söderling ◽

Timo Närhi

Keyword(s):

Protein Adsorption ◽

Blood Coagulation ◽

Gel Electrophoresis ◽

Platelet Rich Plasma ◽

Healing Process ◽

Sol Gel ◽

Blood Protein ◽

Wound Healing Process ◽

Platelet Response ◽

Total N

This in vitro study was designed to evaluate the effect of sol-gel derived TiO2coating on blood coagulation, blood protein adsorption, and platelet response on zirconia surfaces. Square-shaped zirconia (n=96) (10x10x2 mm) was cut, ground, sintered, and finally cleansed ultrasonically in each of acetone and ethanol for 5 minutes. Three experimental groups (n=32) were fabricated: (a) zirconia coated with sol-gel derived TiO2, (b) zirconia coated with sol-gel derived TiO2and treated with ultraviolet (UV) irradiation for 1 hour, and (c) non-coated zirconia as control. The coatings were prepared from tetraisopropyl orthotitanate solution by dip-coating. The thrombogenicity of the specimens was evaluated using a whole blood kinetic clotting time method where the extent of blood clotting was evaluated at 10, 20, 30, 40, 50, and 60 minutes (n=4/time point, total n=24/group). Scanning electron microscope images were taken to observe platelet morphologies after 1-hour incubation with platelet-rich plasma (PRP) (n=5/group). Surface characteristics were visualized using atomic force microscopy (n=1/group). Adsorption of plasma proteins and fibronectin on each surface was studied by gel electrophoresis (n=2/group). Significant differences were observed in blood coagulation between the test groups at 20-, 30-, 40-, and 50-minute time points (p<0.005). UV treated TiO2coated specimens showed fastest blood coagulation followed by TiO2coated and non-coated specimens. Furthermore, platelets appeared at a higher activation state on coated specimens. Gel electrophoresis revealed no difference in protein adsorption among the experimental groups. In summary, TiO2coatings promoted blood coagulation, and it was further enhanced by UV treatment, which has the potential to hasten the wound healing process in vivo.

Download Full-text

Protein Adsorption to Surface Chemistry and Crystal Structure Modification of Titanium Surfaces

Journal of Oral and Maxillofacial Research ◽

10.5037/jomr.2010.1303 ◽

2010 ◽

Vol 1 (3) ◽

Cited By ~ 26

Author(s):

Ryo Jimbo ◽

Mikael Ivarsson ◽

Anita Koskela ◽

Young-Taeg Sul ◽

Carina B. Johansson

Keyword(s):

Crystal Structure ◽

Surface Chemistry ◽

Protein Adsorption ◽

Structure Modification ◽

Titanium Surfaces ◽

Modification Of Titanium

Download Full-text

Pengaruh Pendopingan Karbon Terhadap Struktur Kristal dan Morfologi TIO2

Talenta Conference Series Science and Technology (ST) ◽

10.32734/st.v2i2.492 ◽

2019 ◽

Vol 2 (2) ◽

Author(s):

Frastica Deswardani ◽

Helga Dwi Fahyuan ◽

Rimawanto Gultom ◽

Eif Sparzinanda

Keyword(s):

Thin Film ◽

Crystal Structure ◽

Grain Size ◽

Tio2 Thin Film ◽

Crystal Size ◽

Diffraction Peak ◽

Carbon Doping ◽

Tio2 Anatase ◽

Spray Method ◽

Carbon Analysis

Telah dilakukan penelitian mengenai pengaruh konsentrasi doping karbon pada lapisan tipis TiO2 yang ditumbuhkan dengan metode spray terhadap struktur kristal dan morfologi TiO2. Hasil karakterisasi SEM menunjukkan bahwa penambahan doping karbon dapat meningkatkan ukuran butir. Lapisan TiO2 doping karbon 8% diperoleh ukuran butir terbesar adalah 1.35 μm, sedangkan ukuran tekecilnya adalah 0.45 μm. Sementara itu, untuk lapisan tipis TiO2 didoping karbon 15% memiliki ukuran butir terbesar yaitu 1.76 μm dan terkecil 0.9 μm. Hasil XRD menunjukkan seluruh puncak difraksi lapisan tipis TiO2 dengan doping karbon 8% dan 15% merupakan TiO2 anatase. Ukuran kristal lapisan TiO2 didoping karbon 8% diperoleh sebesar 638,08 Å dan untuk pendopingan 15% karbon ukuran kristal lapisan tipis TiO2 adalah 638,09 Å, hal ini menunjukkan ukuran kristal kedua sampel tidak mengalami perubahan yang signifikan. TiO2 thin film with carbon doping has been successfully grown by spray method. The research on the effect of carbon doping on crystal structure and morfology of TiO2 has been prepared by varying carbon concentration (8% and 15% carbon). Analysis of SEM showed that the addition of carbon may increase the grain size. Thin film of TiO2 doped carbon 8% has the largest grain size 1.35 μm, while the smallest grain size is 0.45 μm. Meanwhile, for thin film TiO2 doped carbon 15% has the largest grain size 1.76 μm and smallest 0.9 μm. The XRD results showed the entire diffraction peak of thin film TiO2 doped carbon 8% and 15% were TiO2 anatase. The crystal size of thin film TiO2 doped carbon 8% was obtained at 638.08 Å and for thin film TiO2 doped carbon 15% the crystalline size of TiO2 thin film was 638.09 Å, this shows that the crystal size of both samples did not change significantly.

Download Full-text

Combined Use of Structure Analysis, Studies of Molecular Association in Solution, and Molecular Modelling to Understand the Different Propensities of Dihydroxybenzoic Acids to Form Solid Phases

Pharmaceutics ◽

10.3390/pharmaceutics13050734 ◽

2021 ◽

Vol 13 (5) ◽

pp. 734

Author(s):

Aija Trimdale ◽

Anatoly Mishnev ◽

Agris Bērziņš

Keyword(s):

Crystal Structure ◽

Molecular Dynamics ◽

Molecular Dynamics Simulations ◽

Structure Analysis ◽

Crystal Structure Analysis ◽

Molecular Association ◽

Hydroxyl Groups ◽

Solid Phases ◽

Solvent Molecules ◽

Dynamics Simulations

The arrangement of hydroxyl groups in the benzene ring has a significant effect on the propensity of dihydroxybenzoic acids (diOHBAs) to form different solid phases when crystallized from solution. All six diOHBAs were categorized into distinctive groups according to the solid phases obtained when crystallized from selected solvents. A combined study using crystal structure and molecule electrostatic potential surface analysis, as well as an exploration of molecular association in solution using spectroscopic methods and molecular dynamics simulations were used to determine the possible mechanism of how the location of the phenolic hydroxyl groups affect the diversity of solid phases formed by the diOHBAs. The crystal structure analysis showed that classical carboxylic acid homodimers and ring-like hydrogen bond motifs consisting of six diOHBA molecules are prominently present in almost all analyzed crystal structures. Both experimental spectroscopic investigations and molecular dynamics simulations indicated that the extent of intramolecular bonding between carboxyl and hydroxyl groups in solution has the most significant impact on the solid phases formed by the diOHBAs. Additionally, the extent of hydrogen bonding with solvent molecules and the mean lifetime of solute–solvent associates formed by diOHBAs and 2-propanol were also investigated.

Download Full-text

Eco-Friendly Colloidal Aqueous Sol-Gel Process for TiO2 Synthesis: The Peptization Method to Obtain Crystalline and Photoactive Materials at Low Temperature

Catalysts ◽

10.3390/catal11070768 ◽

2021 ◽

Vol 11 (7) ◽

pp. 768

Author(s):

Julien G. Mahy ◽

Louise Lejeune ◽

Tommy Haynes ◽

Stéphanie D. Lambert ◽

Raphael Henrique Marques Marcilli ◽

...

Keyword(s):

Organic Pollutant ◽

Sol Gel ◽

Synthesis Method ◽

Specific Treatment ◽

High Specific Surface Area ◽

Crystalline Phases ◽

Tio2 Photocatalysts ◽

Tio2 Anatase ◽

Synthesis Parameters ◽

Calcination Step

This work reviews an eco-friendly process for producing TiO2 via colloidal aqueous sol–gel synthesis, resulting in crystalline materials without a calcination step. Three types of colloidal aqueous TiO2 are reviewed: the as-synthesized type obtained directly after synthesis, without any specific treatment; the calcined, obtained after a subsequent calcination step; and the hydrothermal, obtained after a specific autoclave treatment. This eco-friendly process is based on the hydrolysis of a Ti precursor in excess of water, followed by the peptization of the precipitated TiO2. Compared to classical TiO2 synthesis, this method results in crystalline TiO2 nanoparticles without any thermal treatment and uses only small amounts of organic chemicals. Depending on the synthesis parameters, the three crystalline phases of TiO2 (anatase, brookite, and rutile) can be obtained. The morphology of the nanoparticles can also be tailored by the synthesis parameters. The most important parameter is the peptizing agent. Indeed, depending on its acidic or basic character and also on its amount, it can modulate the crystallinity and morphology of TiO2. Colloidal aqueous TiO2 photocatalysts are mainly being used in various photocatalytic reactions for organic pollutant degradation. The as-synthesized materials seem to have equivalent photocatalytic efficiency to the photocatalysts post-treated with thermal treatments and the commercial Evonik Aeroxide P25, which is produced by a high-temperature process. Indeed, as-prepared, the TiO2 photocatalysts present a high specific surface area and crystalline phases. Emerging applications are also referenced, such as elaborating catalysts for fuel cells, nanocomposite drug delivery systems, or the inkjet printing of microstructures. Only a few works have explored these new properties, giving a lot of potential avenues for studying this eco-friendly TiO2 synthesis method for innovative implementations.

Download Full-text

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.

Download Full-text