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Plant-based Nanomaterials and their Antimicrobial Activity
Published in Mahendra Rai, Chistiane M. Feitosa, Eco-Friendly Biobased Products Used in Microbial Diseases, 2022
Mayuri Napagoda, Priyalatha Madhushanthi, Dharani Wanigasekara, Sanjeeva Witharana
Mesoporous silica nanoparticles have great potential as drug delivery vehicles and their biocompatibility as well as the dynamics of drug release could significantly enhance with a titania surface coating (Farooq et al. 2018). Brezoiu et al. (2020) investigated the nanoconfinement effect of plant extracts into mesopores of silica and titania nanomaterials on the radical scavenging and antimicrobial properties. In this study, polyphenolic extracts of Salvia officinalis and Thymus serpyllum were embedded into the above mesoporous inorganic matrices and the antibacterial, antifungal and radical scavenging activities have been evaluated. The stability of the phytochemicals was enhanced by embedding the extracts into mesoporous inorganic matrices, while the antimicrobial and radical scavenging potencies were higher in extract-loaded materials than the corresponding free extract (Brezoiu et al. 2020).
The Ingestion Pathway
Published in Antonietta Morena Gatti, Stefano Montanari, Advances in Nanopathology From Vaccines to Food, 2021
Antonietta Morena Gatti, Stefano Montanari
Decorating food, especially sweets, with coloured powders is a very common practice. The image is about a powder sold as gold, but in reality, there is no trace of that metal (Fig. 5.11). The particles, almost all of a rather coarse size, are made up of silicon, aluminium, titanium, potassium and iron. It can be assumed that most of these particles are eliminated in the faeces, but it is also necessary to consider how the gastrointestinal walls allow the passage to much larger particles than it is for those which pass through the respiratory system. It should also be added that it is not at all improbable that these indigestible particles, like titania shown in Fig. 5.12, exert an inflammatory action, thereby making the walls even more permeable.
The Spontaneous Induction of Bone Formation by Intrinsically Osteoinductive Bioreactors for Human Patients
Published in Ugo Ripamonti, The Geometric Induction of Bone Formation, 2020
Fujibayashi et al. (2004) reported that titania endowed with osteoinductive potential needed to be chemically and thermally treated. Macroporous bioactive titanium metals showed superior in vitro apatite-forming ability, directly bonding to living bone in vivo (Fujibayashi et al. 2004). As stated above, pure titanium macroporous blocks did not induce bone, raising the critical role of the deposition of apatite as a fundamental key for the induction of bone formation to occur. Apatite was formed after a series of thermal and alkali treatments during the preparation of heterotopically implanted macroporous constructs (Kobuko et al. 1996; Nisiguchi et al. 1999; Fujibayashi et al. 2001; Uchida et al. 2002; Fujibayashi et al. 2004; Takemoto et al. 2006; Kawai et al. 2014).
Analytical review on the biocompatibility of surface-treated Ti-alloys for joint replacement applications
Published in Expert Review of Medical Devices, 2022
Ti alloy surface treatment was performed with plasma spray to enhance mechanical, chemical, or biological properties. To improve the mechanical and biological properties of the HA covering, Titania (TiO2), zirconia (ZrO2), and alumina (Al2O3) are used as a hydroxyl apatite-relieved coating (HA – Ca10(PO4)6OH2) at various levels [74]. HA was observed to be the best suitable ceramic material for surface coverage, but it shows less mechanical compatibility and is fragile [75]. To prevent this, Titania (TiO2), due to its resistance to corrosion, biological characteristics, and ability to enhance cell growth, was preferable as the HA coat [76]. The cover layer protects from releasing the metallic ion’s substratum, while the covering’s particle size influences the layer [77]. By decreasing the particle size, the properties are improved. Nanotechnological developments have recently led to Nanocomposite coating development [78]. HA coating was done with Titania (TiO2) to form and deposit the composite coat [79]. This increases biocompatibility and enhances cell growth. The metal ion cannot be evacuated from the substratum because of the surface film. The particle cover size thus significantly influences the characteristics of the paint in the substratum [80].
Effect of morphology and support of copper nanoparticles on basic ovarian granulosa cell functions
Published in Nanotoxicology, 2020
Alexander V. Sirotkin, Monika Radosová, Adam Tarko, Iris Martín-García, Francisco Alonso
Notwithstanding the limitation to rationalize the obtained results, it is worthwhile mentioning the distinctive behavior observed for hexagonal CuNPs: these nanoparticles are the only ones that reduce the ovarian cell viability and proliferation, inhibiting PCNA accumulation. It is known that the presence of vertices makes metal nanoparticles more reactive. Although this might be one reason of this particular behavior, the fact that the nanoparticles have been prepared in the presence of the somewhat toxic diethylene glycol must not be disregarded. As regards hormone release, the support seems to exert an outstanding role as only CuNPs/TiO2 depletes or suppresses this function. Anatasa titania is composed of chains of distorted TiO6 octahedra possessing undercoordinated atoms at the most abundant nanocrystal faces: i.e. four- or five-fold instead of six-fold-coordinated titanium atoms, as well as two-fold instead of 3-fold-coordinated oxygen atoms (Bourikas, Kordulis, and Lycourghiotis 2014); this makes titania particularly reactive. It is known that oxygen-containing molecules, such as water, can bind five-fold-coordinated titanium atoms (through the water oxygen) and two-fold-coordinated oxygen atoms (through the water hydrogens). Therefore, an interaction of titania with the oxygen atoms of the three hormones or their precursors (more enhanced in the case of testosterone and 17β-estradiol because of the presence of hydroxyl groups in their structure) cannot be ruled out and might account for the particular effect observed for CuNPs/TiO2 on hormone release.
Repeated administration of the food additive E171 to mice results in accumulation in intestine and liver and promotes an inflammatory status
Published in Nanotoxicology, 2019
Laura Talamini, Sara Gimondi, Martina B. Violatto, Fabio Fiordaliso, Federica Pedica, Ngoc Lan Tran, Giovanni Sitia, Federica Aureli, Andrea Raggi, Inge Nelissen, Francesco Cubadda, Paolo Bigini, Luisa Diomede
Titania accumulation in liver was associated to an increased number and size of necroinflammatory foci characterized by the infiltration of monocytes/macrophages expressing F4/80 immunoreactivity. These data suggest that E171 accumulates either in the intravascular phagocytotic macrophages of the liver (Kupffer cells) or in the parenchima by passing through the fenestrated liver sinusoidal endothelial cells (LSECs). Importantly, LSECs lack tight junctions between cells as well as a basal membrane, and contain numerous fenestrae of up to 400nm in diameter (Wisse et al. 1985) thus allowing direct passage of TiO2 particles and accumulation in the space of Disse (i.e. the space between LSECs and hepatocytes). Independently of the primary mechanism by which TiO2 accumulates in the liver, the presence of necroinflammatory foci containing F4/80+ macrophages indicates that TiO2 triggers a mild local inflammatory reaction. Of note, if such mild inflammation persists for long periods of time it might represent a risk factor for complications such as liver fibrosis and hepatocellular carcinoma (HCC) especially in patients with other chronic liver diseases associated with fibrosis and HCC, for example, chronic alcohol ingestion or viral hepatitis (Sitia et al. 2012).