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51.
52.
《Ceramics International》2023,49(12):20251-20260
The goal of biomaterial interest is the ease of the bone tissue regeneration process or the replacement of damaged bone and other tissues with recently generated bone tissue. Calcium silicate (CaSi) bioceramic is a vital material for bone tissue engineering, predominantly for bone repair. Though, the low toughness of calcium silicate imitates its load-bearing applications. The electrophoretic deposition technique was used to coat various concentrations of Zn2+ substituted CaSi on TNT. In this work, a novel as-obtained an appropriate orthopedic implant hybrid material by charged calcium ions of mineralized calcium silicate united with PCL-negatively charged graphene oxide [Zn-CaSi (S1-S3)/PCL (P1-P3)/GO]. Hence, the effectively as-obtained [Zn-CaSi (S1-S3)/PCL (P1-P3)/GO] bone-like apatite on the ternary composite coatings on the surface was proven via XRD, FT-IR, FESEM with EDAX spectra, HR-TEM and BET analyses etc., Moreover, the TNT/S2/P2@GO ternary composite coatings exhibit better mechanical properties and antibacterial activity. The metal ions released from the coatings were calculated via ICP-AES studies. Moreover, the cell viability and also the live/dead staining of MG63 human osteoblasts cells on the subsequent composite coating material for better cell growth in orthopedic applications. 相似文献
53.
《Ceramics International》2023,49(12):20118-20126
When nanomaterials with antibacterial properties were sent to the infected area, it was predicted that infection and related complications could be prevented. The nanoparticles can be designed to possess magnetic and luminescence (magneto-luminescent) properties to be effectively targeted and localized at the infection foci without dispersing into the body. Simultaneously, the magneto-luminescent characteristic of particles allows visualization and confirmation of localized particles at the desired area. In this regard, there are no studies on the use of antibacterial magneto-luminescent bioactive glass for orthopedic applications and the treatment of orthopedic device-related infections. In this study, antibacterial magneto-luminescent 58S bioactive glasses were synthesized by the modified Stöber using coupled with a layer-by-layer assembly approach to possess core/shell particle morphology. SPION/Bioactive glass nanoparticles had an average size of 50 nm and displayed superparamagnetic behavior. While the saturation magnetization value (σs) of the undoped 58S sample was 25.32 emu/g, that of the co-doped sample (2% Eu, 2% Zn) was 21.74 emu/g; this showed that the doping slightly reduced the magnetization value. Europium (Eu) doping of SPION/Bioactive glass nanoparticles induced characteristic red emission originating from Eu emissions belonging to 5D0–7FJ (J = 1–4) transitions and the strongest peak was at 612 nm (electric-dipole transition, 5D0–7F2). Color chromaticity coordinates confirmed emission in the red region. XPS spectrum revealed the existence of Eu and Zn dopant elements in 58S bioactive glass. After soaking characteristic peaks at 31.74° and 45.43° belonging to the hexagonal hydroxyapatite phase were detected in the XRD data, confirming the SEM images. 2% Eu doped SPION/Bioactive glass nanoparticles had the highest osteoblast viability up to 7 days in vitro, while doping the samples with 2% zinc did not yield bone cell viability as high as the Eu doped ones. Importantly, Eu doped SPION/Bioactive glass nanoparticles inhibited gram-positive Staphylococcus aureus (S. aureus) and gram-negative Escherichia coli (E. coli) growth up to 48 h in vitro. The results showed that Eu doping of SPION/Bioactive glass nanoparticles increased osteoblast viability and inhibited bacterial growth, while possessing superparamagnetic properties and exhibiting red luminescence. 相似文献
54.
《Ceramics International》2023,49(20):32377-32387
Herein, we report the wet-chemical synthesis of a ferromagnetic nickel-doped ZnO (Zn1-xNixO) nanocatalyst as a novel and visible-light-driven photocatalyst. Through X-ray diffraction, UV/Vis absorption, electronic studies, and current-voltage experiments, the effect of the ferromagnetic nickel dopant on the structural, optical, morphological, and electrical properties of the synthesized Zn1-xNixO nanocatalyst was studied. The Ni-doping introduced the structural variation in the Zn1-xNixO nanocatalyst, exhibiting a visible light-triggered optical band gap of 2.96 eV and an excellent current conductivity of 6.3 × 10−4 Sm−1. Moreover, the synthesis of the Zn1-xNixO catalyst at the nanoscale enhanced its surface energy, showing a robust affinity to stick with the dye and pathogenic microbes. The synergistic effects of all the mentioned features enable our Zn1-xNixO nanocatalyst to efficiently generate and transport reactive oxygen species (ROS) under visible light illumination. Regarding antibacterial action, the as-synthesized Zn1-xNixO nanocatalyst showed 1.7% higher activity against E. coli than that of the drug Ciprofloxacin. In addition, doped nanocatalysts mineralize almost 97% of the Allura red dye in just 80 min with a constant rate value of 0.036 min−1. The impedance study and post-application XRD proposed that our Zn1-xNixO nanocatalyst has good conductivity and structural stability. Applications studies show the unusual photocatalytic activity of as-synthesized Zn1-xNixO nanocatalysts, which makes it a suitable candidate for industrial discharge treatment applications at the expense of solar light. 相似文献
55.
研究木棉纤维的抗菌性和抗菌机理。木棉纤维经过高温高压灭菌和医用酒精浸泡灭菌,采用吸收法检测其对革兰氏阴性菌大肠杆菌和革兰氏阳性菌金黄色葡萄球菌的抗菌性,并分析了木棉纤维的抗菌机理。结果显示,采用高温高压灭菌的木棉纤维抑菌值要比用医用酒精灭菌测得的小,木棉纤维对大肠杆菌的抑菌率达到了90%以上,优于对金黄色葡萄球菌的;医用酒精处理木棉纤维不会影响其抗菌性;木棉纤维抗菌性能与其所含的黄酮类和三萜类物质以及高度中空的结构有关。认为采用医用酒精灭菌更适合木棉纤维,木棉纤维制品应尽量避免采用高温高压处理。 相似文献
56.
57.
58.
Ya-Na Li 《Polymer-Plastics Technology and Engineering》2013,52(7):725-730
To obtain the antibacterial plastics films, the Ag2O-coated HDPE films were prepared through vacuum evaporation technique via depositing Ag2O on the substrate of high density polyethylene (HDPE) films pretreated by ion bombardment. The pretreatment made the surface polarity and roughness of the substrates improved. The coating was continuous and dense, being of about 17.2 nm thick, and the content of silver ions in it was 7.0020 µg/cm2. The Ag2O-coated HDPE films exhibited strong antibacterial activity for both gram-negative bacteria (E. coli) and gram-positive bacteria (S. aureus). However, the mechanical properties of the composite films slightly dropped in contrast with the HDPE films. 相似文献
59.
Yasodha Sivasothy Wong Keng Chong Abdul Hamid Ibrahim M. Eldeen Shaida Fariza Sulaiman Khalijah Awang 《Food chemistry》2011
The essential oils obtained by hydrodistilation of the leaves and rhizomes of Zingiber officinale var. rubrum Theilade were analysed by capillary GC and GC–MS. Forty-six constituents were identified in the leaf oil, while 54 were identified in the oil from the rhizomes. The leaf oil was clearly dominated by β-caryophyllene (31.7%), while the oil from the rhizomes was predominantly monoterpenoid, with camphene (14.5%), geranial (14.3%), and geranyl acetate (13.7%) the three most abundant constituents. The evaluation of antibacterial activities using the micro-dilution technique revealed that both the leaf and rhizome oils were moderately active against the Gram-positive bacteria Bacilluslicheniformis, Bacillus spizizenii and Staphylococcus aureus, and the Gram-negative bacteria Escherichia coli, Klebsiella pneumoniae and Pseudomonas stutzeri. 相似文献
60.
Anca Giorgiana Grigoras Marieta Constantin Vasile Cristian Grigoras Simona Isabela Dunca Lacramioara Ochiuz 《Reactive and Functional Polymers》2013,73(9):1249-1254
The physico-chemical properties of three grafted pullulans (P) having linked poly(3-acrylamidopropyl)trimethylammonium chloride (pAPTAC) as side chains (P-g-pAPTAC1, P-g-pAPTAC2 and P-g-pAPTAC3 with 22.53, 29.05, and 34.51 (wt.%) of pAPTAC content in polymer, respectively) and possessing polyelectrolyte character were determined by light scattering analysis. All grafted pullulan aqueous solutions were tested in the presence of 0.5 M NaCl, KCl, NaNO3 or KNO3. The biggest associations were recorded in 0.5 M NaCl aqueous solutions for P-g-pAPTAC1, P-g-pAPTAC2 and P-g-pAPTAC3 according to the maximum values for Rg extracted from MALLS (multiangle laser light scattering) measurements. Also, the dominant conformation in salted solution of these polyelectrolytes was random coil as Debye plot analysis revealed. Antibacterial activity was tested by Kirby–Bauer diffusion method and all grafted pullulans dissolved in aqueous solutions of 0.5 M NaCl have developed inhibition zone against Staphylococcus aureus (ATCC 25923). 相似文献