Ionic conductivity properties of amorphous Li–La–Zr–O solid electrolyte for thin film batteries

N+-bombarded multi-walled carbon nanotubes (N+-bombarded MWCNTs), with different nitrogen atomic percentages, were achieved by different N ion beam currents using ion beam-assisted deposition (IBAD) on MWCNTs synthesized by chemical vapor deposition (CVD). Characterizations of N+-bombarded MWCNTs were evaluated by X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), Raman spectroscopy, and contact angle. For comparison, the in vitro cytocompatibility of the N+-bombarded MWCNTs with different N atomic percentages was assessed by cellular adhesion investigation using human endothelial cells (EAHY926) and mouse fibroblast cells (L929), respectively. The results showed that the presence of nitrogen in MWCNTs accelerated cell growth and proliferation of cell culture. The higher nitrogen content of N+-bombarded MWCNTs, the better cytocompatibility. In addition, N+-bombarded MWCNTs with higher N atomic percentage displayed lower platelet adhesion rate. No hemolysis can be observed on the surfaces. These results proved that higher N atomic percentage led N+-bombarded MWCNTs to better hemocompatibility.

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Effect of nitrogen atomic percentage on N+-bombarded MWCNTs in cytocompatibility and hemocompatibility

Influence of power and temperature on properties of sputtered AZO films

A biomaterials surface enabling the induction of tumor cell death is particularly desirable for implantable biomedical devices that directly contact tumor tissues. However, this specific antitumor feature is rarely found. Consequently, an antitumor-cell nanocoating comprised of vanadium dioxide (VO2) prepared by customized reactive magnetron sputtering has been proposed, and its antitumor-growth capability has been demonstrated using human cholangiocarcinoma cells. The results reveal that the VO2 nanocoating is able to interrupt the mitochondrial electron transport chain and then elevate the intracellular reactive oxygen species levels, leading to the collapse of the mitochondrial membrane potential and the destruction of cell redox homeostasis. Indeed, this chain reaction can effectively trigger oxidative damage in the cholangiocarcinoma cells. Additionally, this study has provided new insights into designing a tumor-cell-inhibited biomaterial surface, which is modulated by the mechanism of mitochondria-targeting tumor cell death.

https://scholars.cityu.edu.hk/files/33121428/123.pdf

Vanadium Dioxide Nanocoating Induces Tumor Cell Death through Mitochondrial Electron Transport Chain Interruption.

In this paper active screen plasma nitriding (ASPN) is used to chemically modify the surface of UHMWPE. This is an unexplored and new area of research. ASPN allows the homogeneous treatment of any shape or surface at low temperature; therefore, it was thought that ASPN would be an effective technique to modify organic polymer surfaces. ASPN experiments were carried out at 120 °C using a dc plasma nitriding unit with a 25% N2 and 75% H2 atmosphere at 2.5 mbar of pressure. UHMWPE samples treated for different time periods were characterized by nanoindentation, FTIR, XPS, interferometry and SEM. A 3T3 fibroblast cell line was used for in vitro cell culture experiments. Nanoindentation of UHMWPE showed that hardness and elastic modulus increased with ASPN treatment compared to the untreated material. FTIR spectra did not show significant differences between the untreated and treated samples; however, some changes were observed at 30 min of treatment in the range of 1500–1700 cm−1 associated mainly with the presence of N−H groups. XPS studies showed that nitrogen was present on the surface and its amount increased with treatment time. Interferometry showed that no significant changes were observed on the surfaces after the treatment. Finally, cell culture experiments and SEM showed that fibroblasts attached and proliferated to a greater extent on the plasma-treated surfaces leading to the conclusion that ASPN surface treatment can potentially significantly improve the biocompatibility behaviour of polymeric materials.

/pdf/effect-of-plasma-surface-modification-on-the-57dwpbifht.pdf

Effect of plasma surface modification on the biocompatibility of UHMWPE

In this paper, the adsorption behavior of plasma proteins on the surface of ZnO thin films prepared by radio frequency (RF) sputtering under different sputtering powers was studied. The microstructures and surface properties of the ZnO thin films were investigated by x-ray diffraction (XRD), scanning electron microscopy (SEM), UV–visible optical absorption spectroscopy and contact angle techniques. The results show that the ZnO thin films have better orientation of the (0 0 2) peak with increasing RF power, especially at around 160 W, and the optical band gap of the ZnO films varies from 3.2 to 3.4 eV. The contact angle test carried out by the sessile drop technique denoted a hydrophobic surface of the ZnO films, and the surface energy and adhesive work of the ZnO thin films decreased with increasing sputtering power. The amounts of human fibrinogen (HFG) and human serum albumin (HSA) adsorbing on the ZnO films and reference samples were determined by using enzyme-linked immunosorbent assay (ELISA). The results show that fewer plasma proteins and a smaller HFG/HSA ratio adsorb on the ZnO thin films' surface.

Effect of surface microstructure and wettability on plasma protein adsorption to ZnO thin films prepared at different RF powers

Effect of annealing on structure and haemocompatibility of tetrahedral amorphous hydrogenated carbon films

Tetrahedral amorphous carbon films (ta-C) as promising blood-contacting biomaterials have been prepared by pulsed laser deposition. The structural and optical properties of these films have been studied by scanning electron microscopy, Raman spectroscopy, UV-visible optical absorption spectroscopy and contact angle measurement. Results show that ta-C films with different bond ratios of sp3 C to sp2 C can be obtained by changing the repetition frequency of the pulsed laser during deposition. The blood compatibility of the samples was evaluated by tests of platelet adhesion and kinetic clotting time. The quantity and morphology of the adherent platelets on the surface of samples were investigated by scanning electron microscopy. The haemocompatibility of ta-C films depends on the bond ratio of sp3 C to sp2 C and the better blood compatibility of the samples is attributed to a suitable sp3 C fraction in ta-C films.

Min Chen

Papers

Effect of surface microstructure and wettability on plasma protein adsorption to ZnO thin films prepared at different RF powers

Effect of annealing on structure and haemocompatibility of tetrahedral amorphous hydrogenated carbon films

Structure and Haemocompatibility of Tetrahedral Amorphous Carbon Films Prepared by Pulsed Laser Ablation (S & M 0734)