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Quantum Dots as Biointeractive and Non-Agglomerated Nanoscale Fillers for Dental Resins
Published in Mary Anne S. Melo, Designing Bioactive Polymeric Materials for Restorative Dentistry, 2020
Isadora Martini Garcia, Fabrício Mezzomo Collares
Despite the promising results found for ZnOQDs, traditional syntheses via sol-gel process and self-organization of the nanoparticles with common solvents (such as alcohol, acetone, and methanol) present low yield, making it challenging to develop and to study materials with different amounts of quantum dots. Moreover, as previously stated, the quantum dots must remain in the liquid medium at low temperatures (Meulenkamp 1998) to not agglomerate.
Scintillating quantum dots
Published in Sam Beddar, Luc Beaulieu, Scintillation Dosimetry, 2018
Claudine Nì. Allen, Marie-Ève Lecavalier, Sébastien Lamarre, Dominic Larivière
In recent years, the sol–gel process has been recognized as an extremely useful strategy to encapsulate scintillant in a glassy matrix, providing an alternative to the porous glass diffusion method used by Létant and Wang (2006). The term sol–gel refers to a process in which solid nanoparticles dispersed in a liquid (a sol) agglomerate together to form a continuous 3D network extending throughout the liquid (a gel). The method used to prepare the sol-gel uses a scintillant that cannot typically be introduced into a high-temperature glass melt.
Viruses as Nanomaterials
Published in Devarajan Thangadurai, Saher Islam, Charles Oluwaseun Adetunji, Viral and Antiviral Nanomaterials, 2022
Dushyant R. Dudhagara, Megha S. Gadhvi, Anjana K. Vala
M13 bacteriophages can be assembled layer by layer to form a film to develop “advanced nanoporous materials.” The layer-by-layer assembly was achieved using covalent interaction, which was conducted through 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) crosslinking. The bacteriophage film had a surface porosity of 59% and a roughness of 40%. The substrates were dipped in a TiCl4 solution after layer-by-layer assembly to deposit Ti ions, which were then hydrolyzed to form TiO2 nanoparticles using the sol-gel process. The as-prepared TiO2 film's surface morphology revealed a mesh-like assembly of nanowires 10 nm in diameter. Pore sizes on the surface and within these meshes ranged from 4 to 15 nm. The reaction temperature and time have been shown to be crucial in interconnecting the wires and preventing overgrowth. Since TiO2 can be sensitized with Au for optoelectronic applications, the capacity of the bacteriophage film to embed Au nanoparticles was investigated using dip-and-drop coating. Because of capillary forces, drop coating increased nanoparticle penetration into the network. M13 bacteriophages were used as models for the synthesis of nano-barium titanate (BTO) nanostructures, in contrast to the virus-based, layer-by-layer assembly. Genetically engineered M13 bacteriophages with three glutamates on the N-terminus of the major capsid p8 were incubated with barium glycolates, followed by titanium glycolates. The interaction of viruses with barium glycolates to form a barium containing complex 1 (virus + barium glycolate) was aided by electrostatic interaction. Through electrostatic and hydrogen bonding interactions, complex 1 was eventually coated with titanium glycolates to form titanium- and barium-containing complex 2 (virus + barium glycolate + titanium glycolate). After that, Complex 2 was calcined to form a perovskite crystal structure (BTO). Despite the fact that the viruses were calcined, their fibrous morphology (lengths of 50–100 nm) was preserved. Following that, BTO was spin-coated on a polydimethylsiloxane layer, and indium tin oxide coated with polyethylene terephthalate was applied. The indium tin oxide coated polyethylene terephthalate was used as the top electrode, which formed a sandwich structure for piezoelectric evaluations. The resulting flexible nanogenerator, with a surface area of 6.25 cm2, generated 300 nA of short-circuit current and 6 V of open-circuit voltage. Because of the dispersed configuration of the BTO nanoparticles, which formed from viral templates, the nanogenerator was also more efficient than the BTO nanoparticles assembled with the C nanotubes. The viral template assembly remained stable for up to 21,000 stress cycles (Luo et al. 2015).
Biofilm inhibition and antifouling evaluation of sol-gel coated silicone implants with prolonged release of eugenol against Pseudomonas aeruginosa
Published in Biofouling, 2021
Prasanth Rathinam, Bhasker Mohan Murari, Pragasam Viswanathan
Room temperature-processed acid-base catalyzed sol–gels have been used for various biomedical applications due to their widely accepted bioresorbable and biocompatible properties, tailorable composition and microstructure, excellent prolonged release properties, the ease of introducing multiple functional groups or elements, and the possibility of depositing them on any substrata by using inexpensive and straightforward techniques (Brinker and Scherer 2013). The sol–gel process involves the transition of a solution system from a liquid ‘sol’ (mostly colloidal) into a solid ‘gel’ phase through gelation, condensation and drying processes (Dehghanghadikolaei et al. 2018). Large quantities of biological molecules can be added into the porous solution system and uniformly distributed in the concrete matrix. Thus, sol–gels are prepared as thin films, coatings and hydrogels for fire-retardant, anti-static, water/oil repellent, insect-repellent, antimicrobial and catalytic applications, as well as for the encapsulation of enzymes, proteins, growth factors and antimicrobial agents (Brinker and Scherer 2013).
Intravitreal safety profiles of sol-gel mesoporous silica microparticles and the degradation product (Si(OH)4)
Published in Drug Delivery, 2020
Yaoyao Sun, Kristyn Huffman, William R. Freeman, Michael J. Sailor, Lingyun Cheng
In contrast to electrochemical etching of silicon substrate and subsequent oxidation in the research lab, mesoporous silica particles synthetized by the sol-gel process have been used for drug delivery in various non-ophthalmic applications (Owens et al., 2016; Vlasenkova et al., 2019). The sol-gel process in a large-scale production has many advantages, including significantly higher purity and uniform particle size and pore size. In the current study, sol-gel silica particles without payload are used to generate soluble silicic acid to test cytotoxicity in vitro and sol-gel silica articles with various pore sizes were evaluated in vivo after intravitreal injection. Eye specific information about sol-gel silica particles is meager in literature and the current study aims to explore intravitreal safety of mesoporous sol-gel silica microparticles in the context of a drug delivery vehicle.
Magnetic carbon nanotubes: preparation, physical properties, and applications in biomedicine
Published in Artificial Cells, Nanomedicine, and Biotechnology, 2018
Mehrdad Samadishadlou, Masoud Farshbaf, Nasim Annabi, Taras Kavetskyy, Rovshan Khalilov, Siamak Saghfi, Abolfazl Akbarzadeh, Sepideh Mousavi
In addition to synthesis of high-grade metal or metal oxides/silica nanocomposites, sol–gel process can be employed for synthesis of metal nanocrystals and oxides/carbon hybrid composites. Hydrolysis and condensation of precursor in solution are fundamentals of this process. The quality, shape, structure, size, and properties of the product could be fully governed regulating the parameters including solvent, temperature, concentration of the precursors, the pH, agitation, and so on [61]. MCNTs also can be prepared by the sol–gel process. In a research by Modugno et al. [62], Fe2O3-MWCNTs nanocomposites were synthesized using a modified sol–gel process. As the first step in this method, the MWCNTs surface was activated with carboxylic acid groups and subsequently, using sol–gel process in which the g-Fe2O3 NPs was attached to the MWCNTs surface, at the same time with their synthesis. The main advantages of sol–gel process are low temperature operation which prevents oxidation of precursors and low cost. However, the nature of this process increases the possibility of product contamination which is the major drawback of sol–gel process.