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A sensitive, simple, label-free electrochemical cytosensor was developed to evaluate the anticancer activity of pinoresinol against human cervical carcinoma (HeLa) cells. HeLa cells were immobilised on carboxylated multi-walled carbon nanotubes (c-MWCNTs)/gold nanoparticles (AuNPs) nanocomposite-modified glassy carbon electrodes. Scanning electron microscopy, transmission electron microscopy, Fourier transform-infrared spectroscopy, and X-ray diffractometry were used to characterise the morphology, crystallinity, and composition of the nanocomposites. Cyclic voltammetry was used to characterise and optimise the cytosensor. Both c-MWCNTs and AuNPs increased the electron-transfer rate between the HeLa cells and the electrode, retaining good cell compatibility. The concentration of HeLa cells immobilised on the nanocomposite electrode exhibited a good correlation with the impedance values determined by electrochemical impedance spectroscopy in the range of 10

Vanadium oxide thin films were prepared by DC reactive magnetron sputtering at substrate temperatures ranged from room temperature to 400 °C, and the effects of substrate temperature on microstructure, optical, and electrical properties of the films were analyzed. XRD spectra showed that the main component of the thin films was V2O5 with orthorhombic structure. Tensile stresses exist in the thin films. With increasing substrate temperature, the films gradually changed from amorphous to polycrystalline in nature. High peak transmittance of about 80% for the samples prepared at temperatures less than 300 °C is observed. The optical bandgap of the thin films slightly decreased from 2.51 to 2.44 eV at first, and then increased with increasing substrate temperature. The optical bandgap changes can be attributed to grain size increasing and structural modification of thin films with substrate temperature. All samples had a large sheet resistance of about 106–107 Ω/□ and negative temperature coefficient of resistance (TCR) of about −1.0% K−1. The sheet resistance decreased as the deposition temperature increased, and the TCR presented an initial decrease and then an increasing trend.

Micro-defect is one of key limiting factors in the improvement of the laser-induced damage threshold (LIDT) of thin films. In the present paper, thin films were prepared using the electron-beam evaporation technique with different coating materials and pre-melting processes. The relationships of thin film LIDT with impurity element content and with pre-melting processes were investigated. The experiment results indicate that a number of impurity elements play an important role in the LIDT of the samples. An efficient pre-melting process is necessary to maintain deposition stability, which could also reduce micro-defect density in thin films.