Journal articles: 'Bioactive Thin Film'

1

Tong, X., A. Trivedi, H. Jia, M. Zhang, and P. Wang. "Enzymic Thin Film Coatings for Bioactive Materials." Biotechnology Progress 24, no. 3 (June 6, 2008): 714–19. http://dx.doi.org/10.1021/bp0704135.

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Ma, Q., Y. J. Wang, Cheng Yun Ning, Hai Mei Cheng, and Zhao Yi Yin. "Bioactive Porous Film Produced on Titanium Substrate by Micro-Arc Oxidation." Key Engineering Materials 368-372 (February 2008): 1201–2. http://dx.doi.org/10.4028/www.scientific.net/kem.368-372.1201.

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Porous bioactive thin film on commercially pure titanium substrate was prepared by micro-arc oxidation (MAO) in electrolytic solution, which contained calcium acetate, β-glycerol phosphate disodium salt pentahydrate (β-GP) and lanthanum nitrate. The phases and microstructure of the bioactive films were examined by X-ray diffraction, scanning electron microscopy with energy dispersive X-ray spectrometer and electron probe microanalysis. The results showed that: (1) porous bioactive films with about 10μm were formed on titanium substrate by MAO; (2) phases of the thin films were hydroxyapatite, anatase and rutile; (3) elements of Ca, P, and Ti of films were identified by EDS.

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Sato, Koji, Daisuke Onodera, Mitsuhiro Hibino, and Takeshi Yao. "Development of Bioactive Organic Polymer Coated with Ceramic Thin Films Synthesized from Aqueous Solution." Key Engineering Materials 309-311 (May 2006): 771–74. http://dx.doi.org/10.4028/www.scientific.net/kem.309-311.771.

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Poly methyl methacrylate(PMMA) with mar resistant or poly ethtylene(PE) substrates were surface-treated by applying plasma discharge or alkaline solution. Ceramic thin film comprised of silicon oxide, titanium oxide and zirconium oxide was formed on these surface treated substrates respectively from an aqueous solution, and after the formation of ceramic thin film, titanium oxide thin film was also coated on them from aqueous solution at ordinary temperature and pressure. The thin film coated polymer material was tested in mechanical property. The thin film was hard and the adhesion strength to the organic polymer substrate was very high. The substrate was soaked in SBF and apatite was formed on the substrate. This method is promising for developing hard and soft tissue implants with various mechanical properties as well as high bioactivity.

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ZHAO, YAFAN, CHUANZHONG CHEN, and DIANGANG WANG. "THE APPLICATION OF PULSED LASER DEPOSITION IN PRODUCING BIOACTIVE CERAMIC FILMS." Surface Review and Letters 12, no. 03 (June 2005): 401–8. http://dx.doi.org/10.1142/s0218625x05007177.

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Pulsed laser deposition (PLD) is a relatively new technique for producing thin films. It presents unique advantages for the deposition of bioactive ceramics. The mechanism and characteristics of the technique PLD are introduced. Its applications and current research status in hydroxyapatite and bioglass thin films are reviewed. The effect of processing parameters of PLD, including atmosphere, substrate temperature, laser wavelength and target properties, on the structures and the properties of the hydroxyapatite film, is analyzed in detail. Future application trends are also analyzed.

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Lyutova, E. S., and L. P. Borilo. "Synthesis of bioactive thin-film SiO2 – P2O5 – СаO – TiO2-base composites." Tsvetnye Metally, no. 2 (February 28, 2023): 29–35. http://dx.doi.org/10.17580/tsm.2023.02.04.

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Zhao, Ya Fan, and Ming Da Song. "The Role of the Energy Density in Pulsed Laser Deposition of Bioactive Glass Films." Advanced Materials Research 631-632 (January 2013): 90–94. http://dx.doi.org/10.4028/www.scientific.net/amr.631-632.90.

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Effect of the energy density on the composition, morphology and deposition rate of the bioglass thin films deposited by pulsed laser was studied by energy dispersive spectroscopy (EDS), scanning electron microscopy (SEM), X-ray diffraction (XRD) and crystal lattice monitor. There is slight compositional difference between the film and the target at lower energy density. Morphology of the films is compact with the particles on the surface of them. Structure of the films is amorphous glass and the size of the particles increases with the energy density. Deposition rate increases with the energy density and the energy density threshold of the film growth is about 2.5J/cm2.

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Negut, Irina, Anita Visan, Camelia Popescu, Rodica Cristescu, Anton Ficai, Alexandru Grumezescu, Mariana Chifiriuc, et al. "Successful Release of Voriconazole and Flavonoids from MAPLE Deposited Bioactive Surfaces." Applied Sciences 9, no. 4 (February 22, 2019): 786. http://dx.doi.org/10.3390/app9040786.

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We explored the potential of biomimetic thin films fabricated by means of matrix-assisted pulsed laser evaporation (MAPLE) for releasing combinations of active substances represented by flavonoids (quercetin dihydrate and resveratrol) and antifungal compounds (amphotericin B and voriconazole) embedded in a polyvinylpyrrolidone biopolymer; the antifungal activity of the film components was evaluated using in vitro microbiological assays. Thin films were deposited using a pulsed KrF* excimer laser source which were structurally characterized using atomic force microscopy (AFM) and Fourier transform infrared spectroscopy (FTIR). High-quality thin films with chemical structures similar to dropcast ones were created using an optimum laser fluence of ~80 mJ/cm2. Bioactive substances were included within the polymer thin films using the MAPLE technique. The results of the in vitro microbiology assay, which utilized a modified disk diffusion approach and were performed using two fungal strains (Candida albicans American Type Culture Collection (ATCC) 90028 and Candida parapsilosis American Type Culture Collection (ATCC) 22019), revealed that voriconazole was released in an active form from the polyvinylpyrrolidone matrix. The results of this study show that the MAPLE-deposited bioactive thin films have a promising potential for use in designing combination devices, such as drug delivery devices, and medical device surfaces with antifungal activity.

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Jedlicka, Sabrina S., Jenna L. Rickus, and Dmitry Zemlyanov. "Controllable Surface Expression of Bioactive Peptides Incorporated into a Silica Thin Film Matrix." Journal of Physical Chemistry C 114, no. 1 (December 15, 2009): 342–44. http://dx.doi.org/10.1021/jp907551t.

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Ghosh, Somnath, Tasneem Kausar Ranebennur, and H. N. Vasan. "Study of Antibacterial Efficacy of Hybrid Chitosan-Silver Nanoparticles for Prevention of Specific Biofilm and Water Purification." International Journal of Carbohydrate Chemistry 2011 (January 11, 2011): 1–11. http://dx.doi.org/10.1155/2011/693759.

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Antibacterial efficacy of silver nanoparticles (Ag NPs) deposited alternatively layer by layer (LBL) on chitosan polymer in the form of a thin film over a quartz plate and stainless steel strip has been studied. An eight-bilayer chitosan/silver (Cs/Ag)8 hybrid was prepared having a known concentration of silver. Techniques such as UV-visible spectroscopy, inductively coupled plasma optical emission spectroscopy (ICP-OES), and atomic force microscopy (AFM) were carried out to understand and elucidate the physical nature of the film. Gram-negative bacteria, Escherichia coli (E. coli), were used as a test sample in saline solution for antibacterial studies. The growth inhibition at different intervals of contact time and, more importantly, the antibacterial properties of the hybrid film on repeated cycling in saline solution have been demonstrated. AFM studies are carried out for the first time on the microbe to know the morphological changes affected by the hybrid film. The hybrid films on aging (3 months) are found to be as bioactive as before. Cytotoxicity experiments indicated good biocompatibility. The hybrid can be a promising bioactive material for the prevention of biofilms specific to E. coli and in purification of water for safe drinking.

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Sartori, Barbara, Heinz Amenitsch, and Benedetta Marmiroli. "Functionalized Mesoporous Thin Films for Biotechnology." Micromachines 12, no. 7 (June 24, 2021): 740. http://dx.doi.org/10.3390/mi12070740.

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Mesoporous materials bear great potential for biotechnological applications due to their biocompatibility and versatility. Their high surface area and pore interconnection allow the immobilization of molecules and their subsequent controlled delivery. Modifications of the mesoporous material with the addition of different chemical species, make them particularly suitable for the production of bioactive coatings. Functionalized thin films of mesoporous silica and titania can be used as scaffolds with properties as diverse as promotion of cell growth, inhibition of biofilms formation, or development of sensors based on immobilized enzymes. The possibility to pattern them increase their appeal as they can be incorporated into devices and can be tailored both with respect to architecture and functionalization. In fact, selective surface manipulation is the ground for the fabrication of advanced micro devices that combine standard micro/nanofluids with functional materials. In this review, we will present the advantages of the functionalization of silica and titania mesoporous materials deposited in thin film. Different functional groups used to modify their properties will be summarized, as well as functionalization methods and some examples of applications of modified materials, thus giving an overview of the essential role of functionalization to improve the performance of such innovative materials.

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11

Rau, Julietta V., Angela De Bonis, Mariangela Curcio, Katharina Schuhladen, Katia Barbaro, Giovanni De Bellis, Roberto Teghil, and Aldo R. Boccaccini. "Borate and Silicate Bioactive Glass Coatings Prepared by Nanosecond Pulsed Laser Deposition." Coatings 10, no. 11 (November 18, 2020): 1105. http://dx.doi.org/10.3390/coatings10111105.

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Silicate (13-93) and borate (13-93-B3) bioactive glass coatings were successfully deposited on titanium using the nanosecond Pulsed Laser Deposition technique. The coatings’ microstructural characteristics, compositions and morphologies were examined by a number of physico-chemical techniques. The deposited coatings retain the same functional groups of the targets, are a few microns thick, amorphous, compact and crack free. Their surface is characterized by the presence of micrometric and nanometric particles. The surface topography, investigated by Atomic Force Microscopy, is characterized by spherical or ellipsoidal particles of the 0.2–3 μm size range for the 13-93 silicate bioactive glass film and of the 0.1–1 µm range for the 13-93-B3 borate bioactive glass coating. Equine adipose tissue-derived mesenchymal stem cells (ADMSCs) were applied for biological tests and the osteogenic differentiation activity of cells on the deposited coatings was studied after ADMSCs growth in osteogenic medium and staining with Alizarin Red. Cytocompatibility and osteogenic differentiation tests have shown that thin films retain the biocompatibility properties of the target silicate and borate glass, respectively. On the other hand, no antibacterial activity of the borate glass films was observed, suggesting that ion doping is advisable to inhibit bacterial growth on the surface of borate glass thin films.

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12

Petrović, Suzana, Nevena Božinović, Vladimir Rajić, Danijela Stanisavljević Ninković, Danilo Kisić, Milena J. Stevanović, and Emmanuel Stratakis. "Cell Response on Laser-Patterned Ti/Zr/Ti and Ti/Cu/Ti Multilayer Systems." Coatings 13, no. 6 (June 16, 2023): 1107. http://dx.doi.org/10.3390/coatings13061107.

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Arranged patterns obtained via ultrafast laser processing on the surface of Ti/Cu/Ti/Si and Ti/Zr/Ti/Si thin-film systems are reported. Two differently designed multilayer thin films Ti/Cu/Ti/Si and Ti/Zr/Ti/Si were deposited on silicon using the ion sputtering method. The bioactive surfaces of these systems involve the formation of laser-induced periodic surface structures (LIPSS) in each of the laser-written lines of mesh patterns on 5 × 5 mm areas. The formation of nano- and micro-patterns with an ultra-thin oxide film on the surfaces was used to observe the effects of morphology and proliferation of the MRC-5 cell culture line. To determine whether Ti-based thin films have a toxic effect on living cells, an MTT assay was performed. The relative cytotoxic effect, as a percentage of surviving cells, showed that there was no difference in cell number between the Ti-based thin films and the control cells. There was also no difference in the viability of the MRC-5 cells, except for the Ti/Cu/Ti/Si system, where there was a slight 10% decrease in cell viability.

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13

Teghil, Roberto, Mariangela Curcio, and Angela De Bonis. "Substituted Hydroxyapatite, Glass, and Glass-Ceramic Thin Films Deposited by Nanosecond Pulsed Laser Deposition (PLD) for Biomedical Applications: A Systematic Review." Coatings 11, no. 7 (July 4, 2021): 811. http://dx.doi.org/10.3390/coatings11070811.

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The deposition of thin films of bioactive materials is the most common approach to improve the bone bonding ability of an implant surface. With this purpose, several wet and plasma assisted deposition methods were proposed in the scientific literature. In this review, we considered films obtained by nanosecond Pulsed Laser Deposition (PLD). Since hydroxyapatite (HA) has composition and structure similar to that of the mineral component of the bone, the initial studies focused on the selection of experimental conditions that would allow the deposition of films that retain HA stoichiometry and crystallinity. However, biological apatite was found to be a poorly crystalline and multi-substituted mineral; consequently, the attention of researchers was oriented towards the deposition of substituted HA, glass (BG), and glass-ceramic (BGC) bioactive materials to exploit the biological relevance of foreign ions and crystallinity. In this work, after a description of the nanosecond ablation and film growth of ceramic materials, we reported studies on the mechanism of HA ablation and deposition, evidencing the peculiarities of PLD. The literature concerning the PLD of ion substituted HA, BG, and BGC was then reviewed and the performances of the coatings were discussed. We concluded by describing the advantages, limitations, and perspectives of PLD for biomedical applications.

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14

Peptu, Catalina, Marcel Popa, and Sophia G. Antimisiaris. "Release of Liposome-Encapsulated Calcein from Liposome Entrapping Gelatin-Carboxymethylcellulose Films: A Presentation of Different Possibilities." Journal of Nanoscience and Nanotechnology 8, no. 5 (May 1, 2008): 2249–58. http://dx.doi.org/10.1166/jnn.2008.169.

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Liposome entrapment in films consisting of gelatin (GEL) or GEL/sodium carboxymethylcellulose (NaCMC) mixtures, as a method to alter drug release kinetics from polymeric films and/or incorporate sensitive bioactive molecules in solid films, was investigated. Bulk or thin complex (liposome trapping) films were formed by crosslinking (with glutaraldehyde) solutions of GEL or GEL/NaCMC in presence of calcein-encapsulating or rhodamine-labeled liposomes (Rho-Lip). Rho-Lip were observed by confocal microscopy to be homogenously distributed in the films. Calcein release from films was evaluated for periods up to 25 d, and it was found that several possibilities, concerning the release of the liposome-encapsulated molecule from the films, are offered; (i) Release can be sustained, if large liposomes are entrapped in the films. In this case the liposome-encapsulated molecules are released from the films only after they have been released from the vesicles, and the release can be controlled by modifying the film composition, the network density and/or the film geometry. (ii) Intact small unilamellar liposomes (SUV) can be released from the polymeric films depending on their swelling degree. The later can be controlled by modulating the film composition and amount of crosslinker. Film composition also affects the integrity of the film-entrapped liposomes during the crosslinking process, possibly due its effect on the density of the polymeric network of the film.

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15

Mao, Zhengwei, Lie Ma, Jie Zhou, Changyou Gao, and Jiacong Shen. "Bioactive Thin Film of Acidic Fibroblast Growth Factor Fabricated by Layer-by-Layer Assembly." Bioconjugate Chemistry 16, no. 5 (September 2005): 1316–22. http://dx.doi.org/10.1021/bc049755b.

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Tian, Yi Ping, Shan Shan Wei, Hui Li, and Ling Hong Guo. "Fabrication and Characterization of Bioactive Cancellous-Like Surface on Titanium." Key Engineering Materials 368-372 (February 2008): 1370–73. http://dx.doi.org/10.4028/www.scientific.net/kem.368-372.1370.

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Bioactive porous surface on metal implants are benefit for forming the continuous interface with “mechanical interlocking” and “chemical bonding” between implants and bones. In the present study, the main attention was concentrated on fabricating a porous bioactive surface on Ti substrate. Porous surface was first fabricated by two-step etched. Then thin HA coating was deposited on the pre-treated porous Ti surface by sol-gel method and immediately sintered at 500°C for 1 hour. The structure and morphology of HA coating formed on the porous surface were characterized by thin-film X-ray diffrac- tion and scanning electronic microscopy, respectively. Rietveld method and Warren-Averbach Fourier Transfer Analysis were employed to determine the lattice parameters, crystallite size and micro-strain of HA coating. The SEM results indicated that an interconnecting porous surface with cancellous structure and mean diameter about 1/m was etched on the Ti substrate, and the surface was covered by a thin particle coating. The TF-XRD results testified that the thin coating was poor crystalline HA.

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17

MROZEK, PIOTR. "BIOACTIVE GLASS PARTICLES FIELD-ASSISTED SEALING TO TITANIUM IMPLANT GLASS-BASED COATINGS." Surface Review and Letters 16, no. 01 (February 2009): 1–3. http://dx.doi.org/10.1142/s0218625x09012457.

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This paper reports for the first time the use of field-assisted sealing for bioactive implant coating applications. Field-assisted sealing (anodic bonding) of bioactive glass particles to bioinert glass enamel coating of titanium implant was investigated. Biocompatible titanium oxide interlayer was fabricated by deep thermal oxidation of 80 nm thick Ti thin film previously vacuum evaporated onto polished bioactive glass surface. Bioactive glass particle was anodically bonded via the interlayer to polished surface of bioinert glass enamel coating vacuum deposited onto Ti plate at 860°C. A total of 20 min preheating time with constant temperature increase rate, 5 min bonding time, and 100 V DC voltage were applied during field-assisted bond formation at 530°C in air.

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18

Xiao, Fan, Kanji Tsuru, Satoshi Hayakawa, and Akiyoshi Osaka. "Low Temperature Synthesis of Bioactive TiO₂ Thin Film by Two-Step Treatment." Key Engineering Materials 240-242 (May 2003): 537–40. http://dx.doi.org/10.4028/www.scientific.net/kem.240-242.537.

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Thampi, Sudhin, A. Maya Nandkumar, Vignesh Muthuvijayan, and Ramesh Parameswaran. "Differential Adhesive and Bioactive Properties of the Polymeric Surface Coated with Graphene Oxide Thin Film." ACS Applied Materials & Interfaces 9, no. 5 (January 30, 2017): 4498–508. http://dx.doi.org/10.1021/acsami.6b14863.

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Mousa, Hamouda M., Kamal H. Hussein, Ahmed A. Raslan, Joshua Lee, Heung M. Woo, Chan Hee Park, and Cheol Sang Kim. "Amorphous apatite thin film formation on a biodegradable Mg alloy for bone regeneration: strategy, characterization, biodegradation, and in vitro cell study." RSC Advances 6, no. 27 (2016): 22563–74. http://dx.doi.org/10.1039/c5ra25306c.

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Bioactive films with a nanoplate structure were prepared on the surface of a biodegradable AZ31B magnesium (Mg) alloy via anodization in simulated body fluid (SBF) as an electrolyte to control Mg biodegradability and improve surface bioactivity.

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21

Curcio, Mariangela, Brigida Bochicchio, Antonietta Pepe, Antonio Laezza, Adriana De Stefanis, Julietta V. Rau, Roberto Teghil, and Angela De Bonis. "Mn-Doped Glass–Ceramic Bioactive (Mn-BG) Thin Film to Selectively Enhance the Bioactivity of Electrospun Fibrous Polymeric Scaffolds." Coatings 12, no. 10 (September 29, 2022): 1427. http://dx.doi.org/10.3390/coatings12101427.

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In recent years, significant progress has been made in the development of new technologies to meet the demand for engineered interfaces with appropriate properties for osteochondral unit repair and regeneration. In this context, we combined two methodologies that have emerged as powerful approaches for tissue engineering application: electrospinning to fabricate a nanofibrous polymeric scaffold and pulsed laser deposition to tune and control the composition and morphology of the scaffold surface. A multi-component scaffold composed of synthetic and natural polymers was proposed to combine the biocompatibility and suitable mechanical properties of poly(D,L-lactic acid) with the hydrophilicity and cellular affinity of gelatin. As part of a biomimetic strategy for the generation of bi-functional scaffolds, we coated the electrospun fibers with a thin film of a bioactive glass–ceramic material supplemented with manganese ions. The physico-chemical properties and composition of the bi-layered scaffold were investigated, and its bioactivity, in terms of induced mineralization, was tested by incubation in a simulated body fluid buffer. The processes of the inorganic film dissolution and the calcium phosphate phases growth were followed by microscopic and spectroscopic techniques, confirming that a combination of bioactive glass–ceramics and nanofibrous scaffolds has promising potential in the regeneration of osteochondral tissue due to its ability to induce mineralization in connective tissues.

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22

Negrila, Catalin Constantin, Daniela Predoi, Rodica V. Ghita, Simona Liliana Iconaru, Steluta Carmen Ciobanu, Mirela Manea, Monica Luminita Badea, et al. "Multi-Level Evaluation of UV Action upon Vitamin D Enhanced, Silver Doped Hydroxyapatite Thin Films Deposited on Titanium Substrate." Coatings 11, no. 2 (January 21, 2021): 120. http://dx.doi.org/10.3390/coatings11020120.

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Hydroxyapatite Ca10(PO4)6(OH)2 (HAp) is an important bioactive material for bone tissue reconstruction, due to its highly thermodynamic stability at a physiological pH without bio-resorption. In the present study, the Ag:HAp and the corresponding Ag:HAp + D3 thin films (~200 nm) coating were obtained by vacuum deposition method on Ti substrate. The obtained samples were exposed to different UV irradiation times, in order to investigate the UV light action upon thin films, before considering this method for the thin film’s decontamination. The effects of UV irradiation upon Ag:Hap + D3 are presented for the first time in the literature, marking a turning point for understanding the effect of UV light on composite biomaterial thin films. The UV irradiation induced an increase in the initial stages of surface roughness of Ag:HAp thin film, correlated with the modifications of XPS and FTIR signals. The characteristics of thin films measured by AFM (RMS) analysis corroborated with XPS and FTIR investigation highlighted a process of recovery of the thin film’s properties (e.g., RMS), suggesting a possible adaptation to UV irradiation. This process has been a stage to a more complicated UVA rapid degradation process. The antifungal assays demonstrated that all the investigated samples exhibited antifungal properties. Moreover, the cytotoxicity assays revealed that the HeLa cells morphology did not show any alterations after 24 h of incubation with the Ag:HAp and Ag:HAp + D3 thin films.

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Petkova, Hristina, Ewelina Jarek, Mitko Doychinov, Marcel Krzan, and Elena Mileva. "Synergy in Aqueous Systems Containing Bioactive Ingredients of Natural Origin: Saponin/Pectin Mixtures." Polymers 14, no. 20 (October 16, 2022): 4362. http://dx.doi.org/10.3390/polym14204362.

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Biocompatible and biodegradable ingredients of natural origin are widely used in the design of foam and emulsion systems with various technological applications in the food, cosmetics and pharmaceutical industries. The determination of the precise composition of aqueous solution formulations is a key issue for the achievement of environmentally-friendly disperse systems with controllable properties and reasonable stability. The present work is focused on the investigation of synergistic interactions in aqueous systems containing Quillaja saponins and Apple pectins. Profile analysis tensiometer (PAT-1) is applied to study the surface tension and surface dilational rheology of the adsorption layers at the air/solution interface. The properties and the foam films (drainage kinetics, film thickness, disjoining pressure isotherm, critical pressure of rupture) are investigated using the thin-liquid-film (TLF) microinterferometric method of Scheludko–Exerowa and the TLF-pressure-balance technique (TLF-PBT). The results demonstrate that the structure and stability performance of the complex aqueous solutions can be finely tuned by changing the ratio of the bioactive ingredients. The attained experimental data evidence that the most pronounced synergy effect is registered at a specific saponin:pectin ratio. The obtained information is essential for the further development of aqueous solution formulations intended to achieve stable foams based on mixtures of Quillaja saponins and Apple pectins in view of future industrial, pharmaceutical and biomedical applications.

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Ueda, Masato, Hiroki Sai, Masahiko Ikeda, and Michiharu Ogawa. "Formation of Hydroxyapatite on Titanium Oxides in Simulated Body Fluid under UV Irradiation." Materials Science Forum 654-656 (June 2010): 2257–60. http://dx.doi.org/10.4028/www.scientific.net/msf.654-656.2257.

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Hydroxyapatite (HAp), Ca10(PO4)6(OH)2, is known to precipitate on bioactive materials by soaking in simulated body fluid (SBF). The formation of HAp on TiO2 and CaTiO3 surfaces under continuous ultraviolet (UV) irradiation was investigated in this study. Pure Ti substrates were chemically treated with H2O2/ HNO3 solution at 353 K for 20 min to form a TiO2 gel layer. The samples were then hydrothermally treated with an aqueous NH3 or an aqueous Ca(OH)2 solution in an autoclave at 453 K for 12 h. An adhesive and sufficiently crystallized anatase-type TiO2 film or perovskite-type CaTiO3 film could be synthesized on the Ti surface, respectively. The samples were immersed in SBF in darkness or under UV irradiation. The UV irradiation promoted the formation of HAp, which may be due to the generation of functional Ti-OH or Ti-O groups on both surfaces. On the other hand, the UV light also produces electron-hole pairs in the product films. In TiO2, much photogenerated holes migrated to the surface and repelled the Ca2+ ions in the solution. As a consequence, the UV irradiation suppressed the formation of HAp thin film on the surface of TiO2.

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Morita, Yasuyuki, Toshiki Miyazaki, Eiichi Ishida, and Chikara Ohtsuki. "Apatite-Forming Ability of Organic-Inorganic Hybrids Prepared from Calcium Silicate and Glucomannan." Key Engineering Materials 361-363 (November 2007): 567–70. http://dx.doi.org/10.4028/www.scientific.net/kem.361-363.567.

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So-called bioactive ceramics are used for bone-repairing owing to attractive features such as direct bone-bonding in living body. However, there is limitation on clinical applications due to their inappropriate mechanical properties performances such as higher brittleness and lower fracture toughness than natural bone. To overcome this problem, hybrid materials have been developed by modification of calcium silicate, that is basic component of bioactive ceramics, with organic polymer. It is known that bioactive ceramics bond to bone through bone-like apatite layer which is formed on their surfaces by chemical reaction with body fluid. We attempted preparation of bioactive organic-inorganic hybrids from Glucomannan that is a kind of complex polysaccharide, and calcium silicate. Hybrids were prepared from glucomannan and tetraethoxysilane (TEOS). They were treated with 1M (=mol·m-3) CaCl2 aqueous solution for 24 hours. Then ability of apatite formation on the hybrids was examined in vitro using simulated body fluid (SBF, Kokubo solution). Surface structure of the specimens was examined by thin-film X-ray diffraction (TF-XRD), scanning electron microscopic (SEM) observation. The hybrids with TEOS:Glucomannan= 1:1 to 4:1 in mass ratio formed the apatite in SBF within 3 or 7 d, when they were previously treated with CaCl2 solution.

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Yu, Qi Feng, Bang Cheng Yang, Yao Wu, and Xing Dong Zhang. "Preparation of Bioactive Nanophase Titania Ceramics by Alkali-Heat Treatment." Key Engineering Materials 288-289 (June 2005): 215–18. http://dx.doi.org/10.4028/www.scientific.net/kem.288-289.215.

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In this study, alkali-heat treatment in NaOH solution and heat treatment, which could form amorphous sodium titanate on nanophase titania ceramics surface by conditioning the process, was employed to modify the structure and bioactivity of biomedical titania ceramics. After the nanophase titania ceramics was subjected to alkali-heat treatment, thin film X-ray diffraction and scanning electron microscopy results showed the titania ceramics surfaces were covered by porous sodium titanate. In fast calacification solution (FCS), the alkali-heat treated titania ceramics could induce bonelike apatite formation on its surface. Our results showed that induction of apatite-forming ability on titania ceramics could be attained by alkali-heat treatment. So it was an effective way to prepare bioactive titania ceramics by combining sintering and alkali-heat treatment.

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Борило, Л. П., and Е. С. Лютова. "Influence of Na2O and TiO2 Additives on Properties of Bioactive Thin Film Materials Based SiO2–P2O5–СаO System." Herald of the Bauman Moscow State Technical University. Series Natural Sciences, no. 76 (January 26, 2018): 104–14. http://dx.doi.org/10.18698/1812-3368-2018-1-104-114.

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Wang, Mingyuan, and Jiuyu Gao. "Atomic layer deposition of ZnO thin film on ZrO2 dental implant surface for enhanced antibacterial and bioactive performance." Materials Letters 285 (February 2021): 128854. http://dx.doi.org/10.1016/j.matlet.2020.128854.

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Hwang, Sehoon, Sang Ho Lim, and Seunghee Han. "Highly adhesive and bioactive Ti–Mg alloy thin film on polyether ether ketone formed by PIII&D technique." Applied Surface Science 471 (March 2019): 878–86. http://dx.doi.org/10.1016/j.apsusc.2018.12.080.

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30

Leonor, Isabel B., Francisco Balas, Kawashita Masakazu, Rui L. Reis, Tadashi Kokubo, and Takashi Nakamura. "Biomimetic Apatite Formation on Different Polymeric Microspheres Modified with Calcium Silicate Solutions." Key Engineering Materials 309-311 (May 2006): 279–82. http://dx.doi.org/10.4028/www.scientific.net/kem.309-311.279.

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Bioactive polymeric microspheres can be produced by pre-coating them with a calcium silicate solution and the subsequent soaking in a simulated body fluid (SBF). Such combination should allow for the development of bioactive microspheres for several applications in the medical field including tissue engineering. In this work, three types of polymeric microspheres with different sizes were used: (i) ethylene-vinyl alcohol co-polymer (20-30 'm), (ii) polyamide 12 (10-30 'm) and (iii) polyamide 12 (300 'm). These microspheres were soaked in a calcium silicate solution at 36.5°C for different periods of time under several conditions. Afterwards, they were dried in air at 100°C for 24 hrs. Then, the samples were soaked in SBF for 1, 3 and 7 days. Fourier transformed infrared spectroscopy, thin-film X-ray diffraction, and scanning electron microscopy showed that after the calcium silicate treatment and the subsequent soaking in SBF, the microspheres successfully formed a bonelike apatite layer on their surfaces in SBF within 7 days due to the formation of silanol (Si-OH) groups that are quite effective for apatite formation.

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Lopes, Ana I. F., David M. Pereira, M. Sameiro T. Gonçalves, A. Gil Fortes, and Elisabete M. S. Castanheira. "Nanosystems for the Encapsulation and Release of Plant Extracts with Insecticidal Activity." Chemistry Proceedings 3, no. 1 (November 14, 2020): 39. http://dx.doi.org/10.3390/ecsoc-24-08332.

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Encapsulation in suitable nanostructures is a relevant strategy for the preservation and controlled release of bioactive compounds, allowing a safe application. In this work, dichloromethane extracts of Mentha suaveolens Ehrh. and Phytolacca americana L. were encapsulated in chitosan nanostructures and liposomes of soybean lecithin, considering their potential as biopesticides. Liposomes were prepared either by thin film hydration or ethanolic injection methods. For chitosan, the ionic gelation technique was used. The nanosystems were characterized regarding their size and polydispersity. Encapsulation efficiencies of the extracts were determined (being higher than 60%) and the release profiles were measured. Liposomes generally allowed a delayed release of the extracts, while chitosan nanosystems were suitable for a faster and complete release of the potential bioinsecticides.

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Borilo, Lyudmila P., Ekaterina S. Lyutova, and Larisa N. Spivakova. "Рroperties of Bioactive Thin-Films Based on System SiO₂-P₂O₅-CаO and SiO₂-P₂O₅-СаO-Na₂O Obtained by Sol-Gel Method." Key Engineering Materials 683 (February 2016): 306–11. http://dx.doi.org/10.4028/www.scientific.net/kem.683.306.

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Thin films were synthesized from alcohol film-forming solutions based on tethraethoxysilane, phosphoric acid, calcium chloride and sodium chloride using sol-gel method. Thin films were produced on the single-crystal silicon substrates (model substrate) by extraction at a velocity of 5 mm/s following by heat treatment at a temperature of 60°С for 20 minutes and at a temperature of 600°С for 1 hour. During the experiment it was established that film-forming solutions are usable only for 2 to 7 days from the moment of preparation. Using thermal and infra-red – spectroscopic analysis main stages of oxide system formation were retraced. According to data from x-ray phase analysis phases CaClH2PO4∙H2O, Ca (H2PO4)2∙H2O, CaHPO4∙2H2O, Ca2SiO4∙H2O, Ca5(PO4)3Cl и CaSiO3,NaCl, CaCl2, H2PO4·H2O, Ca5(PO4)3Cl, SiO2 are being registered in the sample. Biological activity of the received material was evaluated in SBF environment. Presence of the sodium oxide in the system leads to the increase in the bioactivity of the material. Such material intensively exchanges with solution in calcium ions and phosphate-ions; silanol groups fix calcium ions, furthering the formation of the layer of amorphous calcium phosphates gradually crystallizing in hydroxyapatite, and other calcium phosphates.

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Safaie, Naghmeh, Holly Jones-Taggart, and Amirkianoosh Kiani. "High Intensity Laser Induced Reverse Transfer: Solution for Enhancement of Biocompatibility of Transparent Biomaterials." Coatings 9, no. 9 (September 17, 2019): 586. http://dx.doi.org/10.3390/coatings9090586.

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Bioactive glass is used extensively in biomedical applications due to its quality and effectiveness in tissue regeneration. Bioactive glasses are able to interact with biological systems and can be used in humans to improve tissue regeneration without any side effects. Bioactive glass is a category of glasses that maintain good contact with body organs and remain biocompatible for a long time after implementation. They have the potential to form a hydroxyapatite surface as a biocompatible layer after immersion in body fluid. In this research, glass biocompatibility was modified using a deposition method called the high intensity laser induced reverse transfer (HILIRT) method and they were utilized as enhanced-biocompatibility bioactive glass (EBBG) with a correspondent nanofibrous titanium (NFTi) coating. HILIRT is a simple ultrafast laser method for improving implants for biomedical applications and provides a good thin film of NFTi on the glass substrate that is compatible with human tissue. The proposed method is a non-chemical method in which NFTi samples with different porosities and biocompatibilities are synthesized at various laser parameters such as power and frequency. Physical properties and cell compatibility and adhesion of these NFTi before and after immersion in simulated body fluid (SBF) were compared. The results indicate that increasing laser intensity and frequency leads to more NFTi fabrication on the glass with no toxicity and better cell interaction and adhesion.

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Borilo, L. P., and E. S. Lyutova. "Synthesis and properties of bioactive thin-film materials based on the SiO2–P2O5–СаO and SiO2–P2O5–CaO–TiO2 systems." Inorganic Materials 53, no. 4 (April 2017): 400–405. http://dx.doi.org/10.1134/s0020168517040033.

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Parashar, Pratima. "Synthesis of Silver Nanocomposite with Poly(vinylpyrollidone) and Poly(4-vinylpyridine) for Antimicrobial Activity." Advanced Materials Research 772 (September 2013): 9–14. http://dx.doi.org/10.4028/www.scientific.net/amr.772.9.

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Dispersing silver nanoparticles homogeneously into a polymer matrix byex situmethods is difficult because of the easy agglomeration of nanoparticles. Therefore, convenient and effective ways of preparing Ag nanoparticles in polymer materials are still in strong demand. Vacuum deposited thin discontinuous silver films on the composite of Poly (vinylpyrrolidone) (PVP) and poly (4-vinylpyridine) (P4VP) is an in situ and eco friendly method. Films on softened PVP give rise to a very high room temperature resistance approaching that of the substrate resistance indicating non uniform formation of silver clusters. On the other hand, films on softened P4VP gives rise to a room temperature resistance in the range of a few tens to a few hundred MW/, which is desirable for device applications due adequate size and uniform dispersal of silver clusters in P4VP. Silver films on PVP/P4VP blend show room temperature resistances in the desirable range indicating uniform subsurface formation of silver films on PVP/P4VP. The Electrical, optical and plasmonic response of Ag NP onto thin layers of PVP/P4VP shows encapsulation of nanoparticles. Silver nanocomposite film exhibits characteristic UV absorbance spectrum at a wavelength of 430 nm, due to the surface plasmon resonance of nanosized silver. Silver ions being bioactive killed bacteria on infected wounds on living tissue and led physician to use wound dressing containing silver sulfadiazine and Ag NP to treat external infections. Silver lining food helps in treating various remedies and ailments.

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Jinga, Sorin-Ion, Michael Skokin, Bogdan-Stefan Vasile, Izabela Constantinoiu, Dana Miu, Mihaela Bacalum, and Cristina Busuioc. "Development of Vitroceramic Coatings and Analysis of Their Suitability for Biomedical Applications." Coatings 9, no. 10 (October 16, 2019): 671. http://dx.doi.org/10.3390/coatings9100671.

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Within the field of tissue engineering, thin films have been studied to improve implant fixation of metallic or ceramic materials in bone, connective tissue, oral mucosa or skin. In this context, to enhance their suitability as implantable devices, titanium-based substrates received a superficial vitroceramic coating by means of laser ablation. Further, this study describes the details of fabrication and corresponding tests in order to demonstrate the bioactivity and biocompatibility of the newly engineered surfaces. Thus, the metallic supports were covered with a complex material composed of SiO2, P2O5, CaO, MgO, ZnO and CaF2, in the form of thin layers via a physical deposition techniques, namely pulsed laser deposition. The resulting products were characterized by X-ray diffraction, Fourier-transform infrared spectroscopy, scanning and transmission electron microscopy coupled with energy dispersive X-ray spectroscopy, selected area electron diffraction, and electron energy loss spectroscopy. It was found that a higher substrate temperature and a lower working pressure lead to the highest quality film. Finally, the samples biocompatibility was assessed and they were found to be bioactive after simulated body fluid soaking and biocompatible through the MTT cell viability test.

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Luo, Sheng Lei, Zhan Hua Yang, Ming Lin, Xin Xu, Yan Hui Zhang, Bin Guo, and Li Li Dong. "Characterization and Bioactivity of Ti-6Al-4V Alloy Dental Implant Surface Treated by SLA Technique." Advanced Materials Research 926-930 (May 2014): 965–68. http://dx.doi.org/10.4028/www.scientific.net/amr.926-930.965.

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Superior quality dental implant surface was achieved by an air-isolation technique of sand-blasted, large-grit, acid-etched (SLA) treatment. The experiment was conducted in an air-isolation conditions of sand-blasting and acid-etching. The surface microstructures, chemical compositions, and bioactive properties of treated Ti-6Al-4V implants were examined using scanning electron microscope (SEM), energy dispersive spectrometer (EDS) and simulated body fluid (SBF) immersion test. Research results revealed that the air-isolation SLA (A-SLA) treated implant, which was coated with SBF thin liquid film and sandblasted for 20 s, exhibited better hydroxyapatite (HA)-inducing ability owing to its favorable wettability.

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Colovic, Bozana, Dejan Markovic, and Vukoman Jokanovic. "Nucleation of biomimetic hydroxyapatite." Serbian Dental Journal 58, no. 1 (2011): 7–15. http://dx.doi.org/10.2298/sgs1101007c.

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Introduction. The aim of the study was to assess the formation of biomimetic calcium hydroxyapatite (HAP) on the surface of different substrates. Material and Methods. Silica coated stainless steel tapes and thin polymer films (alginate, cellulose, poly lactide-co-glycolide - PLGA) deposited on hydroxyapatite scaffold were used as substrate. Supersaturated simulated body fluid (SBF) and SBF combined with Fetal Calf Serum (FCS) or Eagle?s Minimum Essential Medium (EMEM) were used as bioactive liquid medium where biomimetic nucleation of HAP occurred. Infrared spectroscopy with Fourier transformation was used to analyze the formed phases, while scanning electron microscopy indicated the morphology of nucleated phase. Results. The results of measuring the mass with volume adjustments done by the BET method showed that the thickness of the film of nucleated calcium hydroxyapatite depended on the time that samples spent soaked in SBF-in as well as the type of selected biomimetic medium. Conclusion. Biomimetic calcium hydroxyapatite is possible to produce by self nucleation on different substrates in the presence of simulating body fluid.

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Wang, Hui, Bang Cheng Yang, Qi Feng Yu, Dayi Wu, and Xing Dong Zhang. "In Vitro Bioactivity of Composite of Nanophase Titania/Bioactive Glass-Ceramic in Simulated Body Fluid." Key Engineering Materials 288-289 (June 2005): 171–74. http://dx.doi.org/10.4028/www.scientific.net/kem.288-289.171.

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Titania ceramics is lack of bone-bonding ability even if it has excellent biocompatibility. Recently, it is even found that the nanophase titania ceramics could enhance the proliferation of osteoblasts. If the bone-bonding ability of this material is improved, it would be a potential bone replacement material. Bioactive glass-ceramic (BGC) is provided with the best bioactivity in biomaterials. In this study, the apatite formation ability and the mechanic properties of titania ceramic were investigated by the accession of BGC. Four samples: TiO2 ceramic, TiO2 +10%BGC, TiO2 +20%BGC and BGC were prepared respectively. These ceramics were exposed to a simulated body fluid (SBF) for 7, 14 and 21d. Scanning electron microscopy (SEM), energy dispersive X-ray detector (EDX) and thin film X-ray diffraction (TF-XRD) results showed that the apatite formation of the ceramics was improved by adding BGC into nanophase titania ceramic. The mechanical analysis showed the biomechanical compatibility was also improved by adding BGC into nanophase titania ceramic.

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Chen, Lijuan, Bowen Yue, Zhiming Liu, Yali Luo, Lu Ni, Zhiyong Zhou, and Xuemei Ge. "Study on the Preparation, Characterization, and Stability of Freeze-Dried Curcumin-Loaded Cochleates." Foods 11, no. 5 (February 28, 2022): 710. http://dx.doi.org/10.3390/foods11050710.

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Curcumin (CUR), a polyphenolic substance extracted from plants, has extensive pharmacological activities. However, CUR is difficult to be absorbed in the body due to its poor stability and low solubility. Studies have found that cochleates can be used as a new delivery system to encapsulate bioactive agents for the purpose of improving its stability and bioavailability. In this study, thin-film dispersion and trapping methods were used to prepare curcumin-loaded cochleates (CUR-Cochs). Then CUR-Cochs were characterized and the encapsulation efficiency was determined by HPLC. In addition, the freeze-drying process of CUR-Cochs was studied and related characterization was performed. CCK-8 assay was used to detect the cytotoxicity of cochleates carrier. Additionally, H2O2-induced cellular oxidative damage model were used to evaluate its antioxidant capacity. The results showed that the structure of CUR-Cochs was a spiral cylinder with an average particle size of 463.8 nm and zeta potential of −15.47 mV. The encapsulation efficiency was the highest (83.66 ± 0.8)% with 1:50 CUR-to-lipid mass ratio. In vitro results showed that cochleates had negligible cytotoxicity and owned antioxidant capacity, which provided the possibility for their applications in food and medicine. In general, the method herein might be a promising method to encapsulate CUR for further use as a bioactive agent in functional foods.

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Monteiro, Luís P. G., João Borges, João M. M. Rodrigues, and João F. Mano. "Unveiling the Assembly of Neutral Marine Polysaccharides into Electrostatic-Driven Layer-by-Layer Bioassemblies by Chemical Functionalization." Marine Drugs 21, no. 2 (January 27, 2023): 92. http://dx.doi.org/10.3390/md21020092.

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Marine-origin polysaccharides, in particular cationic and anionic ones, have been widely explored as building blocks in fully natural or hybrid electrostatic-driven Layer-by-Layer (LbL) assemblies for bioapplications. However, the low chemical versatility imparted by neutral polysaccharides has been limiting their assembly into LbL biodevices, despite their wide availability in sources such as the marine environment, easy functionality, and very appealing features for addressing multiple biomedical and biotechnological applications. In this work, we report the chemical functionalization of laminarin (LAM) and pullulan (PUL) marine polysaccharides with peptides bearing either six lysine (K6) or aspartic acid (D6) amino acids via Cu(I)-catalyzed azide-alkyne cycloaddition to synthesize positively and negatively charged polysaccharide-peptide conjugates. The successful conjugation of the peptides into the polysaccharide’s backbone was confirmed by proton nuclear magnetic resonance and attenuated total reflectance Fourier-transform infrared spectroscopy, and the positive and negative charges of the LAM-K6/PUL-K6 and LAM-D6/PUL-D6 conjugates, respectively, were assessed by zeta-potential measurements. The electrostatic-driven LbL build-up of either the LAM-D6/LAM-K6 or PUL-D6/PUL-K6 multilayered thin film was monitored in situ by quartz crystal microbalance with dissipation monitoring, revealing the successful multilayered film growth and the enhanced stability of the PUL-based film. The construction of the PUL-peptide multilayered thin film was also assessed by scanning electron microscopy and its biocompatibility was demonstrated in vitro towards L929 mouse fibroblasts. The herein proposed approach could enable the inclusion of virtually any kind of small molecules in the multilayered assemblies, including bioactive moieties, and be translated into more convoluted structures of any size and geometry, thus extending the usefulness of neutral polysaccharides and opening new avenues in the biomedical field, including in controlled drug/therapeutics delivery, tissue engineering, and regenerative medicine strategies.

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González-Henríquez, Carmen M., Fernando E. Rodríguez-Umanzor, Nicolas F. Acuña-Ruiz, Gloria E. Vera-Rojas, Claudio Terraza-Inostroza, Nicolas A. Cohn-Inostroza, Andrés Utrera, Mauricio A. Sarabia-Vallejos, and Juan Rodríguez-Hernández. "Fabrication and Testing of Multi-Hierarchical Porous Scaffolds Designed for Bone Regeneration via Additive Manufacturing Processes." Polymers 14, no. 19 (September 27, 2022): 4041. http://dx.doi.org/10.3390/polym14194041.

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Bone implants or replacements are very scarce due to the low donor availability and the high rate of body rejection. For this reason, tissue engineering strategies have been developed as alternative solutions to this problem. This research sought to create a cellular scaffold with an intricate and complex network of interconnected pores and microchannels using salt leaching and additive manufacturing (3D printing) methods that mimic the hierarchical internal structure of the bone. A biocompatible hydrogel film (based on poly-ethylene glycol) was used to cover the surface of different polymeric scaffolds. This thin film was then exposed to various stimuli to spontaneously form wrinkled micropatterns, with the aim of increasing the contact area and the material’s biocompatibility. The main innovation of this study was to include these wrinkled micropatterns on the surface of the scaffold by taking advantage of thin polymer film surface instabilities. On the other hand, salt and nano-hydroxyapatite (nHA) particles were included in the polymeric matrix to create a modified filament for 3D printing. The printed part was leached to eliminate porogen particles, leaving homogenously distributed pores on the structure. The pores have a mean size of 26.4 ± 9.9 μm, resulting in a global scaffold porosity of ~42% (including pores and microchannels). The presence of nHA particles, which display a homogeneous distribution according to the FE-SEM and EDX results, have a slight influence on the mechanical resistance of the material, but incredibly, despite being a bioactive compound for bone cells, did not show a significant increase in cell viability on the scaffold surface. However, the synergistic effect between the presence of the hydrogel and the pores on the material does produce an increase in cell viability compared to the control sample and the bare PCL material.

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Duta, Liviu, and Andrei Popescu. "Current Status on Pulsed Laser Deposition of Coatings from Animal-Origin Calcium Phosphate Sources." Coatings 9, no. 5 (May 24, 2019): 335. http://dx.doi.org/10.3390/coatings9050335.

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The aim of this paper is to present the current status on animal-origin hydroxyapatite (HA) coatings synthesized by Pulsed Laser Deposition (PLD) technique for medical implant applications. PLD as a thin film synthesis method, although limited in terms of surface covered area, still gathers interest among researchers due to its advantages such as stoichiometric transfer, thickness control, film adherence, and relatively simple experimental set-up. While animal-origin HA synthesized by bacteria or extracted from animal bones, eggshells, and clams was tested in the form of thin films or scaffolds as a bioactive agent before, the reported results on PLD coatings from HA materials extracted from natural sources were not gathered and compared until the present study. Since natural apatite contains trace elements and new functional groups, such as CO32− and HPO42− in its complex molecules, physical-chemical results on the transfer of animal-origin HA by PLD are extremely interesting due to the stoichiometric transfer possibilities of this technique. The points of interest of this paper are the origin of HA from various sustainable resources, the extraction methods employed, the supplemental functional groups, and ions present in animal-origin HA targets and coatings as compared to synthetic HA, the coatings’ morphology function of the type of HA, and the structure and crystalline status after deposition (where properties were superior to synthetic HA), and the influence of various dopants on these properties. The most interesting studies published in the last decade in scientific literature were compared and morphological, elemental, structural, and mechanical data were compiled and interpreted. The biological response of different types of animal-origin apatites on a variety of cell types was qualitatively assessed by comparing MTS assay data of various studies, where the testing conditions were possible. Antibacterial and antifungal activity of some doped animal-origin HA coatings was also discussed.

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Dulski, Mateusz, Jacek Balcerzak, Wojciech Simka, and Karolina Dudek. "Innovative Bioactive Ag-SiO2/TiO2 Coating on a NiTi Shape Memory Alloy: Structure and Mechanism of Its Formation." Materials 14, no. 1 (December 29, 2020): 99. http://dx.doi.org/10.3390/ma14010099.

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In recent years, more and more emphasis has been placed on the development and functionalization of metallic substrates for medical applications to improve their properties and increase their applicability. Today, there are many different types of approaches and materials that are used for this purpose. Our idea was based on a combination of a chemically synthesized Ag-SiO2 nanocomposite and the electrophoretic deposition approach on a NiTi shape memory substrate. As a result, silver-silica coating was developed on a previously passivated alloy, which was then subjected to sintering at 700 °C for 2 h. The micrometer-sized coat-forming material was composed of large agglomerates consisting of silica and a thin film of submicron- and nano- spherical-shaped particles built of silver, carbon, and oxygen. Structurally, the coatings consisted of a combination of nanometer-sized silver-carbonate that was embedded in thin amorphous silica and siloxy network. The temperature impact had forced morphological and structural changes such as the consolidation of the coat-forming material, and the partial coalescence of the silver and silica particles. As a result, a new continuous complex ceramic coating was formed and was analyzed in more detail using the XPS, XRD, and Raman methods. According to the structural and chemical analyses, the deposited Ag-SiO2 nanocomposite material’s reorganization was due to its reaction with a passivated TiO2 layer, which formed an atypical glass-like composite that consisted of SiO2-TiO2 with silver particles that stabilized the network. Finally, the functionalization of the NiTi surface did not block the shape memory effect.

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Mubeen, Hajera, and Abdul Mannan. "Formulation and Optimization of Guggul Lipid Phytosomal Gel of Thymoquinone Using 22 Factorial Design." International Journal of Pharmaceutical Sciences and Drug Research 13, no. 04 (March 3, 2020): 371–78. http://dx.doi.org/10.25004/ijpsdr.2021.130402.

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Thymoquinone is a bioactive principal constituent of Nigella Sativa. Thymoquinone is hydrophobic, having low water solubility and less permeability. The study aimed to formulate and optimize Thymoquinone loaded phytosomes using guggul lipid by thin-film method to enhance permeation and stability. 2 factor 2 level design (22 ) using SigmaTech software was employed contour plots were used to predict the responses. The two independent variables used were: the amount of guggul lipid (X1), amount of cholesterol (X2); and the responses included entrapment efficiency (Y1), in-vitro drug release (Y2), and particle size (Y3). The optimized formulation of Thymoquinone phytosomes was incorporated into Carbopol 934 gel base and 0.4% thymoquinone phytosomal gel was prepared. The phytosomal gel was evaluated. The stability study was performed, and phytosomal gel formulation was found stable at 4°C for 45 days.

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Rhee, Sang Hoon, Yong Keun Lee, and Bum Soon Lim. "Evaluation of a Chitosan Nano-Hybrid Material Containing Silanol Group and Calcium Salt as a Bioactive Bone Graft." Key Engineering Materials 284-286 (April 2005): 765–68. http://dx.doi.org/10.4028/www.scientific.net/kem.284-286.765.

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A bioactive chitosan-siloxane nano-hybrid material was newly developed and evaluated for the potential application as a bone graft material. The chitosan which can be dissolved in organic solvent was synthesized by the reaction with phtalic anhydride (Ph-Chitosan) and it was then reacted with 3-isocyanatopropyl triethoxysilane (Si-Chitosan) in dimethylformamide. Following this, the Si-Chitosan was hydrolyzed and condensed to yield a hybrid sol-gel material (Si-O-Chitosan). The gelation was carried out for 1 week at ambient condition in a covered Teflon mold with a few pinholes and then dried under vacuum at room temperature for 48 h. The bioactivity of the chitosan nano-hybrid material was evaluated by examining the apatite forming ability in the simulated body fluid (SBF). The surface microstructure and functional groups of the specimen was analyzed by field emission scanning electron microscopy and Fourier transformed infrared spectroscopy, respectively. The crystal phases of the specimen before and after the bioactivity testing were analyzed by thin film X-ray diffractometry. Newly developed chitosan nano-hybrid material showed apatite-forming ability in the SBF within 1 week soaking and this ability was believed to come from the silanol group formed on the surface of Si-O-Chitosan and calcium salt which increased the ionic activity product of apatite in the SBF.

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Karacan, Ipek, Joshua Chou, Besim Ben-Nissan, Innocent J. Macha, Sophie Cazalbou, and Bruce Milthorpe. "Multifunctional-Dual Drug Delivery Poly-Lactic Acid Biocomposite Coating with Hydroxyapatite for Bone Implants." Key Engineering Materials 782 (October 2018): 212–17. http://dx.doi.org/10.4028/www.scientific.net/kem.782.212.

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The new novel implant designs include the functionality of advanced drug delivery systems in order to improve osteointegration and to inhibit the implant-related post-operative infections. In this research, Ti6Al4V metallic implants were coated with the multifunctional-dual slow drug delivery coating which includes a polymeric matrix system based on a poly-lactic acid thin film and a bioactive ceramic hydroxyapatite. This system consists of two different kinds of pharmaceuticals, which are gentamicin and simvastatin. It is reported in this paper that the simvastatin and gentamicin containing poly-lactic acid coating which was applied uniformly and successfully with and without hydroxyapatite microspheres. Most importantly, the release rate of drugs was controlled with PLA matrix and HAp microspheres which have different dissolution rates in order to prevent the high dosages causing adverse side-effects of drugs.

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Szesz, Eduardo Mioduski, G. B. de Souza, Emanuel Santos, and Neide K. Kuromoto. "Nanomechanical Properties of Bioactive Ti Surfaces Obtained by NaOH-Based Anodic Oxidation and Alkali Treatment." Key Engineering Materials 493-494 (October 2011): 524–29. http://dx.doi.org/10.4028/www.scientific.net/kem.493-494.524.

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Titanium has been used in the production of dental implants and orthopedic prostheses due to the low tendency to corrosion and good biocompatibility. Meanwhile, the surface of titanium is not bioactive. Several surface treatments have been developed to make the surface of such metals bioactive. The aim of this work was to evaluate two of these modification processes in commercially pure titanium grade 2, both of them using NaOH solutions: the anodic oxidation and the alkali treatment. The surface morphology was evaluated by SEM/EDS, the crystal structure by XRD, and the mechanical properties and scratch resistance by instrumented indentation. The anodic oxidation (AO) was carried out using NaOH electrolyte 0.1 mol/L and constant current density of 150 mA/cm² for one minute. The alkaline treatment (AT) was performed by soaking the Ti sample in NaOH 5 mol/L solution at 60 °C for 24 hours; after this, the sample was heat treated at 600 °C for one hour in atmospheric air. The AO produced a TiO2 layer on Ti, whereas a thin sodium titanate layer was obtained by AT. Each surface modification resulted in a specific morphology, but both of them presented the increase in roughness as a common characteristic. The alkali treated Ti surfaces showed the lowest elastic modulus and hardness values. The largest increase in hardness between the treated surfaces was obtained for Ti after anodic oxidation. Scratch test indicates that the TiO2 film from AO has higher strength to tangential loading than the Ti substrate. In addition, for the Ti submitted to AT, the scratch test indicates that the modified surface layer has a poor adhesion with the substrate. Based on these results it is possible to conclude that, using NaOH solutions, Ti surfaces treated by anodic oxidation present improved mechanical properties than the alkali-treated ones.

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Neacsu, Ionela Andreea, Laura Vasilica Arsenie, Roxana Trusca, Ioana Lavinia Ardelean, Natalia Mihailescu, Ion Nicolae Mihailescu, Carmen Ristoscu, Coralia Bleotu, Anton Ficai, and Ecaterina Andronescu. "Biomimetic Collagen/Zn2+-Substituted Calcium Phosphate Composite Coatings on Titanium Substrates as Prospective Bioactive Layer for Implants: A Comparative Study Spin Coating vs. MAPLE." Nanomaterials 9, no. 5 (May 3, 2019): 692. http://dx.doi.org/10.3390/nano9050692.

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Synthesis of biomimetic materials for implants and prostheses is a hot topic in nanobiotechnology strategies. Today the major approach of orthopaedic implants in hard tissue engineering is represented by titanium implants. A comparative study of hybrid thin coatings deposition was performed by spin coating and matrix-assisted pulsed laser evaporation (MAPLE) onto titanium substrates. The Collagen-calcium phosphate (Coll-CaPs) combination was selected as the best option to mimic natural bone tissue. To accelerate the mineralization process, Zn2+ ions were inserted by substitution in CaPs. A superior thin film homogeneity was assessed by MAPLE, as shown by scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) microscopy. A decrease of P-O and amide absorbance bands was observed as a consequence of different Zn2+ amounts. A variety of structural modifications of the apatite layer are then generated, which influenced the confinement process towards the collagen template. The in-vitro Simulated Body Fluid (SBF) assay demonstrated the ability of Coll/Zn2+-CaPs coatings to stimulate the mineralization process as a result of synergic effects in the collagen-Zn2+ substituted apatite. For both deposition methods, the formation of droplets associated to the growth of CaPs particulates inside the collagen matrix was visualized. This supports the prospective behavior of MAPLE biomimetic coatings to induce mineralization, as an essential step of fast implant integration with vivid tissues.

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Seo, Do Won, J. G. Kim, Yun Hae Kim, and Chin Myung Whang. "Apatite Formation on PDMS-Modified SiO₂-CaO-P₂O₅ Hybrids Prepared with Different P₂O₅ Content by Sol-Gel Method." Materials Science Forum 449-452 (March 2004): 1121–24. http://dx.doi.org/10.4028/www.scientific.net/msf.449-452.1121.

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Bioactive ORMOSILS (organically modified silicate), PDMS-CaO-SiO2-P2O5 with five different P2O5 content (0, 0.01, 0.03, 0.06, 0.09 mol%) have successfully been synthesized by sol-gel process. The hybrids have been prepared with polydimethylsiloxane (PDMS), tetraethoxysilane (TEOS), calcium nitrate tetrahydrate [Ca(NO3)2 4H2O] and triethyl phosphate (TEP) as starting materials and subsequently soaked into the simulated body fluid (SBF) for different period of time and the bioactivity of hybrids was determined by examining the apatite formation on the surface of the specimen by FT-IR, Thin-Film X-ray Diffraction, and Scanning Electron Microscopy (SEM). All of the prepared samples with different P2O5 content showed in vitro bioactivity. It was observed that the increase in P2O5 content up to 0.03 mole % increases the apatite formation compared to P2O5- free hybrids. However, further increase in P2O5 concentration slows down the formation of the apatite layer most probably due to the decrease of pH of SBF by dissolution of a large amount of phosphate ions.

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Journal articles on the topic 'Bioactive Thin Film'

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