Viruses as Nanomaterials
Devarajan Thangadurai, Saher Islam, Charles Oluwaseun Adetunji in Viral and Antiviral Nanomaterials, 2022
Genetic modification on CPMV can increase the exterior surface affinity with metals and metalloids. For example, Steinmetz et al. (2009b) explained that CPMV can be genetically modified to surface display a dodecapeptide that allows silica attachment and mineralization. The peptide particles stimulated the deposition of a 2 nm layer of silica on the modified CPMV surface after treatment with the tetraethylorthosilicate and aminopropyltriethoxysilane as precursor agents. In another case, a chimeric CPMV was modified to contain a surface-subjected metal-attaching peptide, which promoted metallization through iron and platinum after treatment with salts and successive subjection to a reducing agent (Shah et al. 2009). In this study, the chimeric CPMV was covered with iron and platinum to a thickness of 1 nm. Genetic modification of CPMV was performed to insert capsid surface-exposed cysteine residues (that are not generally present on the external surface of wild type CPMV) at defined sites (Blum et al. 2004; 2005); these can connect preformed gold nanoparticles with their thiol groups. The attached gold nanoparticles were connected with each other via di-thiolated linkers containing metal particles. Eventually, the surface lysine residues of the CPMV were chemically attached to biotin by EDC carbodiimide conjugation. Because of the metal coating, the modified CPMV particles were observed to be highly conductive; furthermore, this conductance caused the interaction and binding of avidin to biotin, hence making an effective biosensor (Blum et al. 2011).
Multimodality probes for cardiovascular imaging
Yi-Hwa Liu, Albert J. Sinusas in Hybrid Imaging in Cardiovascular Medicine, 2017
Alternatively, nanoparticles can be coated with inert matrices such as silica, providing a stable and water soluble matrix for containment of molecular probes including Gd-DTPA, QDs, iron oxide, or optical agents rhodamine ortris(bipyridine)ruthenium(II)-chloride (Ru(bpy)) (Kim et al. 2007; Lee et al. 2006; Rieter et al. 2007a; 2007b; Santra et al. 2005; Yang et al. 2008). Synthesis of silica nanoparticles is achieved by reverse microemulsion mixing of surfactant, oil, and water to synthesize nanoparticles in multiple nanoreactions, as well as subsequent addition of silica shells by condensation with tetraethylorthosilicate. This layering process can be repeated to incorporate further QDs and functionalities within the nanoparticle, as has been demonstrated with gadolinium-containing gold flecked nanoparticles with size selection achieved by water/surfactant ratio separation (Sharma et al. 2008). Silica nanoparticles have been prepared in a variety of sizes (30–200 nm diameter).
Boron, Manganese, Molybdenum, Nickel, Silicon and Vanadium
Judy A. Driskell, Ira Wolinsky in Sports Nutrition, 2005
Ingested silicon has a relatively low order of toxicity. About the only pathological condition that may occur with a high intake of silicon is urolithiasis. Most silicon compounds, especially silicon dioxide compounds, are essentially nontoxic to humans when taken orally. Magnesium trisilicate, an over-the-counter antacid, has been used by humans for more than 40 years with only minimal apparent deleterious effects reported. In addition to urolithiasis, a high intake of silicon may interfere with the absorption or utilization of some essential nutrient, particularly zinc. An antagonism between zinc and silicon results in high dietary silicon’s decreasing the zinc concentrations in plasma and tissues of rats.166,167 The amount of dietary silicon used to show the antagonism was extremely high in one study;167 the rats were fed 400 mg Si/kg body weight as sodium metasilicate in drinking water for the last 6 weeks of an 18-week experiment. In the other study,166 the effect of a 270-mg Si/kg diet as tetraethylorthosilicate on decreasing plasma zinc was significant only in zinc-deficient rats.
Microencapsulation of reactive isocyanates for application in self-healing materials: a review
Published in Journal of Microencapsulation, 2021
Amanda N. B. Santos, Demetrio J. dos Santos, Danilo J. Carastan
Inorganic materials can also be incorporated into the shell structure to improve its stability. Wu et al. (2014) produced microcapsules with hybrid silica/polyurea shells, combining interfacial polymerisation and in situ sol-gel process in an oil-in-water emulsion, to enhance thermal stability and solvent resistance. Gum arabic (surfactant) aqueous solution was prepared and the oil phase (a mixture of commercial MDI pre-polymer and HDI) was added to form the emulsion system. A diluted solution of polyethylenimine (PEI) was added dropwise into the reaction medium. The pre-hydrolysed product of tetraethyl orthosilicate (TEOS) was introduced after 30 min followed by the addition of ammonium hydroxide solution (NH4OH). The reaction followed at room temperature for 1 h. The synthesis procedure is schematically represented in Figure 4.
Effect and mechanism of paclitaxel loaded on magnetic Fe3O4@mSiO2-NH2-FA nanocomposites to MCF-7 cells
Published in Drug Delivery, 2023
Yun Ni, Peng Deng, Ruitong Yin, Ziye Zhu, Chen Ling, Mingyi Ma, Jie Wang, Shasha Li, Ruijiang Liu
Cetyltrimethylammonium bromide (CTAB) (1.0 g) was added into 180 mL of deionized water containing 2 mL ammonium hydroxide and dissolved completely using ultrasound. Next, 35 mL diethyl ether and 50 mL ethanol were added into the mixture and stirred continuously at room temperature (25 °C). Magnetic Fe3O4 nanoparticles (0.2 g) were dispersed in anhydrous ethanol (10 mL) by ultrasound. Tetraethyl orthosilicate (TEOS) (2 mL) was added after stirring for 10 min, followed by vigorous stirring at room temperature for 2 h. The obtained products were separated under an external magnetic field, washed with deionized water and ethanol, and vacuum dried at 70 °C for 12 h. The products were then dispersed in 50 mL of acidic ethanol and refluxed for 8 h (Fang et al. 2019). This process was repeated three times. Magnetic Fe3O4@mSiO2 nanocomposites were obtained via centrifugation, washing, and drying. Acidic ethanol contained 1% glacial acetic acid. The magnetic Fe3O4@mSiO2 nanocomposites were characterized using FTIR, dynamic light scattering (DLS), SEM, TEM, BET, and vibrating sample magnetometer (VSM).
A novel dendritic mesoporous silica based sustained hydrogen sulfide donor for the alleviation of adjuvant-induced inflammation in rats
Published in Drug Delivery, 2021
Yue Yu, Zhou Wang, Qinyan Yang, Qian Ding, Ran Wang, Zhaoyi Li, Yudong Fang, Junyi Liao, Wei Qi, Keyuan Chen, Meng Li, Yi Zhun Zhu
SPRC was synthesized as we reported previously (Wang et al. 2009). Tetraethyl orthosilicate (TEOS) was purchased from Aladdin Reagent Co., Ltd (Shanghai, China). Cetyltrimethylammonium chloride (CTAC) solution (25 wt % in H2O), 3-aminopropyltriethoxysilane (APTES), triethanolamine (TEA) and decahydronaphthalene (DHA) were all purchased from Sigma Aldrich (St Louis, USA). Complete Freund’s Adjuvant (CFA), propargylglycine (PAG), BMDM medium (Iscove’s modified Dulbecco’s medium supplemented with 10% fetal calf serum, 100 μ mL−1 penicillin, 100 μg mL−1 streptomycin, 10 mM thioglycerol), human macrophage-colony stimulating factor (M-CSF), sodium hydroxide, hydrochloric acid, acetonitrile, methanol, toluene, anhydrous ethanol, sodium sulfide, monobromobimane (MBB), diethylenetriaminepentaacetic acid (DTPA), sulfosalicylic acid and hydrocortisone were purchased from Macklin Industrial Corporation (Shanghai, China). Elisa kit of TNF-α, IL-1β, IL-6 and IL-10 were purchased from MultiSciences (Hangzhou, China).
Related Knowledge Centers
- Chemical Compound
- Ethanol
- Silicic Acid
- Silicon Dioxide
- Iupac Nomenclature of Inorganic Chemistry
- Chemical Formula
- Alkoxide
- Silicon Tetrachloride
- Silicone
- Zeolite