Journal of Advances in Nanomaterials

9

Authors: Peitao Liu, Qiang Xu, Daqiang Gao, Shoupeng Shi, Baorui Xia

Visible light-responsive Fe3O4@g-C3N4 nanocomposites were prepared by hydrothermal method with g-C3N4 nanosheets as the substrates. The photocatalytic performances of the Fe3O4@g-C3N4 nanocomposites were evaluated in photo Fenton-like discoloration of RhB dye using H2O2 as an oxidant under visible-light irradiation. Meanwhile, the reusability and magnetic properties were also investigated. The results revealed that the Fe3O4@g-C3N4 nanocomposites showed considerable photocatalytic activity, and exhibited excellent reusability with almost no change after four runs, and more importantly, Fe3O4@g-C3N4 nanocomposites could be recovered magnetically. Therefore, the fabricated Fe3O4@g-C3N4 nanocomposite photocatalyst is a promising candidate for energy conversion and environmental remediation.

11

Authors: Xin-Hua Tian, Yu-Hua Wang, Feng Wei, Xiao-Ning Lin, Lei Ren

An excellent gene vector is of great importance for the development of the gene therapy. Gelatin–siloxane nanoparticles (GS NPs) with controlled size and surface charge were synthesized through a two-step sol–gel process for gene vector. In order to increase the efficiency of tumour targeting, HIV-derived Tat peptide and TTA1, a kind of modified RNA aptamer, were further grafted onto GS NPs (GS-PEG-TTA1/TAT NPs). It was demonstrated in this article that gelatin-siloxane nanoparticles (GS NPs) have the significant characteristic of being innocuous, small, covered with positive charge and even have been modified with PEG, TTA1, and TAT. The modified nanoparticles, GS-PEG-TTA1/TAT, not only have the ability of crossing the cell membrane with DNA accompanied effectively, but also could target the U251 cells and impel the DNA express right in the cells with the help of aptamer TTA1.

18

Authors: Gladius Lewis

Several shortcomings of the alloys that are used to fabricate a number of currentgeneration biomedical implants, such as Ti-6Al-4V alloy for the femoral stem of a total hip replacement and AZ3 Mg alloy for the scaffold of a fully bioabsorbable coronary artery stent, are well-known. Examples of these shortcomings are limited bioactivity/osseointegration (in the case of Ti-based alloys) and high corrosion rate (in the case of Mg-based alloys). It is now recognized that a nanostructured hydroxyapatite (nanoHA) coating on the substrate of a bioalloy can increase bioactivity and reduce corrosion of the substrate. A large number of nanoHA deposition methods and a variety of characterization techniques/methods have been used to obtain an assortment of properties of the coating, the coated specimens, and the coating-substrate interface. Examples of these deposition methods are electrophoretic deposition and radiofrequency magnetron sputtering and some of the most frequently used characterization techniques/methods are x-ray diffraction, Fourier transform infrared spectroscopy, transmission electron microscopy, scanning electron microscopy, atomic force microscopy, immersion tests in a biosimulating solution at 37 o C, and culturing in cells extracted from humans. Among the properties obtained are the morphology, thickness, size of the nanoHA; degree of crystallinity of the coating; and the adhesive strength and corrosion rate in an aqueous biosimulating solution at 37o C. The present work is a comprehensive review of the very large body of literature in this field, with the focal topics being essential steps in a deposition method, discussion of the influence of deposition method variables on myriad coating properties (for a given deposition method), and identification of the shortcomings of the literature, and, hence, outlines of ten suggested directions for future research.