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During the corona virus (COVID-19) pandemic, there was a sharp increase in the need for diagnostic tests that could detect the presence of SARS-CoV-2 virus or its antibodies quickly and reliably. An important type in the group of diagnostic tests are rapid antigen lateral flow immuno-assay (LFIA) tests, which operate on the immuno-chromatographic principle with the lateral flow of analyte. Clinical practice in the last year has shown that such diagnostic tests can be effective in preventing the spread of the SARS-CoV-2 virus.The development, and, thus, the production of the rapid antigen LFIA tests, is influenced by a number of factors that determine their sensitivity and accuracy indirectly. These factors are directly dependent on the type of antibody produced, which is formed as an immune response when infected with the virus. The production of the rapid antigen LFIA tests is associated with the appropriate selection of basic components that determine the type and quality of these tests. The basic components include: substrates and membranes, antigens, antibody labels and compatible buffers. The correct choice of membranes and their materials is crucial to compiling an effective rapid antigen LFIA test. This study therefore presents a comparative analysis of four commercially available SARS-CoV-2-rapid LFIA tests using state-of-the-art characterisation techniques scanning electron microscopy (SEM), inductively coupled plasma-optical emission spectrometry (ICP-OES), environmental scanning electron microscope / energy-dispersive X-ray spectroscopy (ESEM/EDX), Fourier-transform infrared spectroscopy / attenuated total reflection (FTIR/ATR) for the individual components. The obtained results were the starting point for the development and assembling of our own rapid antigen LFIA test based on gold nanoparticles as antibody labels.

Experimental study and numerical model for the thermo-mechanical properties in continuous casting (CC) of Cu-Al alloys is presented. This is a prerequisite basis for further development of Cu based shape memory alloys (SMA) with various alloying elements (like Ni or Mn). A coupled thermo-mechanical numerical simulation of the CC process is implemented and applied to the full non-equilibrium process conditions. In the experimental part, we used simple yet effective vertical continuous casting system. For the quantitative comparison, we implemented a special temperature measurement system within a graphite crystalliser that enables us to monitor the temperature profile at several spots around the solidification front in real time. The present analysis of the various process parameters’ effect on the solidification process includes: casting speed, thermal contact conductivity, liquid metal temperature, and cooling system set up. For microstructural examination we prepared samples from rods that were subsequently investigated by optical microscopy, scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDXS) analysis. Comparisons of the experimental results and numerical simulation were carried out. We developed a comprehensive numerical simulation model that quantitatively describes non-equilibrium time- dependent temperature profile, solid fraction and microstructure features in as cast state. Results from the coupled thermo-mechanical and microstructural simulations compare favourably with experimental data suggesting the casting speed as a key parameter in process optimisation.

Our work deals with the problem of producing a complex metal-ceramic composite using the processes of internal oxidation (IO) and severe plastic deformation. For this purpose, Cu-Al alloy with 0.4wt.% of Al was used. IO of sample serves in the first step of the processing as a means for attaining a fine dispersion of nanosized oxide particles in the metal matrix. Production technology continues with repeated application of severe plastic deformation (SPD) of the resulting metal matrix composite to produce the bulk nanoscaled structural material. SPD was carried out with equal channel angular pressing (ECAP), which allowed that the material could be subjected to an intense plastic strain through simple shear. Microstructural characteristics of one phase and multiphase material was studied on internally oxidized Cu with 0.4wt.% of Al sample composed of one phase copper-aluminum solid solution in the core and fine dispersed oxide particles in the same matrix in the mantle region. In this manner AFM, X-ray diffraction and Raman spectroscopy were used. Local structures in plastically deformed samples reflect presence of $Cu$, $CuO$, $Cu_2O$, $Cu_4O_3$ or $Al_2O_3$ structural characteristics, depending on type of sample.