This paper presents a test stand for testing alternating current electrical parameters of Cu–SiO₂ multilayer nanocomposite structures obtained by the dual-source non-reactive magnetron sputtering method (resistance, capacitance, phase shift angle, and dielectric loss angle tangent δ). In order to confirm the dielectric nature of the test structure, measurements in the temperature range from room temperature to 373 K were carried out. The alternating current frequencies in which the measurements were made ranged from 4 Hz to 7.92 MHz. To improve the implementation of measurement processes, a program was written to control the impedance meter in the MATLAB environment. Structural studies by SEM were conducted to determine the effect of annealing on multilayer nanocomposite structures. Based on the static analysis of the 4-point method of measurements, the standard uncertainty of type A was determined, and taking into account the manufacturer’s recommendations regarding the technical specification, the measurement uncertainty of type B.

The aim of the study was to present a method for assessing the condition of cell culture by measuring the impedance of cells cultured in the presence of nickel. For this purpose, an impedance measurement technique using nickel comb capacitors was used. The capacitor electrodes were made using a thin film magnetron sputtering. In the experimental part, the culture of cells of mouse fibroblasts on the prepared substrate was performed. The cell culture lasted 43 hours and showed that the presented technique allows it to be used to analyze the effect of nickel on cells.

This work investigated the electrical, dielectric, and magnetic properties of ferrofluids containing Fe₃O₄ nanoparticles and their composites with chitosan (30–100 cP and 100–300 cP), relevant to magnetic hyperthermia. The nanoparticles were synthesized by coprecipitation and characterized using impedance spectroscopy, X-ray diffraction, scanning microscopy with X-ray microanalysis, Mössbauer spectroscopy, and calorimetry. The study showed that the chitosan coating altered the textural properties of Fe₃O₄, reducing the specific surface area from 76.3 m²/g to 68.9–72.5 m²/g. The zeta potential and particle size showed strong pH dependence. Impedance measurements showed that the conductivity of ferrofluids was frequency- and temperature-dependent, with both metallic and dielectric conductivity observed. The complex dielectric permittivity exhibited Maxwell–Wagner–Sillars interface polarization. Calorimetry revealed that specific absorption rate (SAR) ranged from 11.4 to 23.4 W/g, depending on the chitosan concentration and type, while the chitosan coating reduced SAR by 12–40%. These results confirm that the electrical and dielectric parameters of ferrofluids significantly influence their thermal capabilities, which is important for optimizing magnetic hyperthermia therapy when energy dissipation is considered in bio-heat models.

This paper explores the possibility of using the impedance measurement method used to monitor morphological changes in culture cells for use in cultures in the presence of an electromagnetic field generated by a mobile phone. For this purpose, we used Electric Cell–Substrate Impedance Sensing (ECIS), which is a real-time, label-free, impedance-based method to study cell behaviors in tissue culture. As part of the work, a device enabling the connection in a climatic chamber was prepared without the need to interfere with environmental conditions, and a test culture of mouse fibroblasts was performed. The device based on the Arduino UNO programmable platform worked like a mobile phone. During cell proliferation, it was connected to the device three times and a change in electrical parameters in the measuring system was observed. During the phone call, there was a clear change in the values of the measured parameters. However, analysis of the obtained results indicated that there was little or no effect of the presence of the electromagnetic field on the cell culture, while the observed changes in the values of impedance, resistance, and capacitance are most likely due to the separation of positive and negative medium ions in the electromagnetic field. The application of the presented method seems possible; however, in order to eliminate the separation of ions, a different type of antenna should be designed to emit a homogeneous field to the entire well.

This article presents a method of obtaining multilayer NiFe-SiO2 nanocomposites by non-reactive magnetron sputtering. Structures with different numbers and thicknesses of layers were made on two different types of dielectric substrates. Electrical parameters were tested in the frequency range from 4 Hz to 8 MHz, as well as measurements of the surface roughness of the substrates. Based on the results, the influence of design parameters and the aging effect on the AC properties of the structures was determined.