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The work and leisure environments
Published in Stephen Battersby, Clay's Handbook of Environmental Health, 2023
Jonathan Hayes, Stuart Wiggans
These materials can be either formed unintentionally such as those made through pollution, or they may be engineered for products such as cosmetics or sports gear. Nanoparticles such as zinc oxide have been used within sunscreens and cosmetics for some time. The Friends of the Earth’s report Nanomaterials, sunscreens and cosmetics: Small ingredients, big risks [4], detailed 116 products that were commercially available at that time.116
Recent Trends in Nanomaterial-Based Advanced Oxidation Processes for Degradation of Dyes in Wastewater Treatment Plants
Published in Maulin P. Shah, Sweta Parimita Bera, Günay Yıldız Töre, Advanced Oxidation Processes for Wastewater Treatment, 2022
Samuel S. Mgiba, Vimbai Mhuka, Nomso C. Hintsho-Mbita, Nilesh S. Wagh, Jaya Lakkakula, Nomvano Mketo
Zinc oxide has good chemical and thermal stability. It has also a high recombination ration of photo-induced electron-hole pairs. However, ZnO has a poor response to visible light and a possibility of photo corrosion. This has an impact on the photocatalytic activities of ZnO. Researchers used doping to minimize these drawbacks. Europium (Eu) was used in different concentrations with ZnO to degrade methylene blue and methylene orange under solar radiation. A hole was created by exciting an electron on the conductive band. Since it was coated with europium, the Eu3+ ion prevented the recombination of the hole by trapping the electron to create superoxide radicals. A high amount of superoxide radical was produced by introducing more of the Eu3+ ion to the ZnO structure. Dyes were attacked by the hydroxyl radical through a hole transfer. The formed intermediates during degradation also proceeded with self-degradation or were degraded with reactive oxidation species. This yielded 62% degradation of dye in 150 minutes [34].
Recent Advances in Materials Science and Engineering Contributing to the Infection Diseases
Published in Peerawatt Nunthavarawong, Sanjay Mavinkere Rangappa, Suchart Siengchin, Mathew Thoppil-Mathew, Antimicrobial and Antiviral Materials, 2022
Sabarish Radoor, Aswathy Jayakumar, Jasila Karayil, Jyothi Mannekote Shivanna, Jyotishkumar Parameswaranpillai, Suchart Siengchin
Zinc oxide is commonly used in rubber, paints, textiles, pharmaceuticals, and food packaging. The essential properties of zinc oxide, which increases its usage in biomedical fields, are antibacterial, antimicrobial, UV blocking properties, and photocatalytic disinfecting agents [47-48]. When compared to silver nanoparticles, zinc oxide nanoparticles are less toxic and safe to use in humans as well as animals. Zinc oxide nanoparticles have been incorporated into polymers to generate antibacterial materials [49]. For instance, Silvestre et al. [50] developed a nanocomposite by incorporating ZnO into isotactic polypropylene (iPP) and investigate its biocide effect. The antibacterial study revealed that nanoparticles’ exposure time and concentration play an important role in the retardation of bacterial growth. The composite loaded with 95% iPP and 5% zinc nanoparticle exhibit maximum reduction of bacteria (99.9%) when the exposure time was 48 h.
Synthesis of Persea americana extract based hybrid nanoflowers as a new strategy to enhance hyaluronidase and gelatinase inhibitory activity and the evaluation of their toxicity potential
Published in Inorganic and Nano-Metal Chemistry, 2022
Emrah Bor, Ufuk Koca Caliskan, Ceren Anlas, Goksen Dilsat Durbilmez, Tulay Bakirel, Nalan Ozdemir
Copper and zinc are widely preferred in the preparation of organic-inorganic hybrid nanoflowers to augment the effect of plant extracts, since they are the most beneficial minerals for skin health. In human skin, copper has role in the synthesis and stabilization of ECM skin proteins, as well as stimulates dermal fibroblast proliferation, upregulates collagen and elastin fiber components, serves as a cofactor of superoxide dismutase and tyrosinase enzymes. [25] Zinc is a co-factor for over 1000 enzymatic reactions that have roles in a variety of organic activities such as development, differentiation, and cell growth. Various Zn-related molecules such as matrix metalloproteinases, integrins, alkaline phosphatase, and Zn finger proteins are involved in the wound healing process. In addition, zinc oxide and copper oxide nanoparticles are extensively used in cosmetic and dermatological applications (such as a barrier in sunscreens or antibacterial in cosmetics). [25,26]
Antimicrobial properties of nanoparticles in the context of advantages and potential risks of their use
Published in Journal of Environmental Science and Health, Part A, 2021
Zinc oxide is used in the pharmaceutical industry, as a component of many preparations, including dusting powder, ointments and antiseptic pastes, where its antibacterial and anti-inflammatory properties are used. Lu et al.[40] investigated the size, shape, and composition of commercial sunscreens containing ZnO in order to characterized its surface, dispersion, and antimicrobial properties. Another advantage of ZnO NPs is its color. Zinc oxide in its macroscopic form is colorless and transparent, while in its nanometric form it is white. This property is particularly beneficial where the appearance and esthetics are of great importance. An example of such an application is the addition of ZnO NPs to orthodontic products. Kachoei et al.[41] modified stainless steel wires by coating zinc oxide nanoparticle, what reduce friction between wires and orthodontic brackets. ZnO NPs coating decreasing frictional forces has a double advantage. On one hand, it may increase the durability of applicated dental elements and on the other, modified material remains white.
Zinc-containing precursor dependence of hydrothermal method for the synthesis of N-doped ZnO photocatalysts
Published in Chemical Engineering Communications, 2021
Minh Chau Ta Xuan, Tuan Ngoc Tran, Claire Botto, Tram Anh Ha, The Luan Nguyen, Tien Khoa Le
In the first step, different zinc-containing precursors were respectively prepared to be used for the further hydrothermal process. Firstly, the required amount of Zn(NO3)2.6H2O was dissolved in distilled water to obtain 300 mL of 0.1 mol.L−1 zinc nitrate solution (solution A) and 100 mL of 0.2 mol.L−1 zinc nitrate solution (solution B). Next, 0.1 mol.L−1 aqueous NaOH solution was slowly added to 300 mL of solution A during 1 h under continuous magnetic stirring (700 rpm) to reach pH 8. The obtained zinc hydroxide precipitate was filtered, washed with distilled water and dried in a Memmert oven (Germany) at 120 °C during 1 h. Then after, an amount of zinc hydroxide was annealed at 500 °C for 2 h in air atmosphere using a CWF Carbolite furnace (UK) with a heating rate of 1 °C min−1 to obtain pure zinc oxide.