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The electrokinetic possibilities of separation and concentration of S.aureus bacteria in human whole blood (test mixture) were studied using a new design of a four-electrode biosensor chip format with transparent microelectrodes. In the measurements, a closed cell was used, into which the test mixture was poured. The electrokinetic movement of bacteria during concentration was observed when AC voltage was applied to the first and second annular external electrodes, and DC voltage was applied to the third and fourth semicircular central electrodes. The process of separation of erythrocytes and concentration of bacteria was recorded by an optical method. It is shown that the concentration of bacteria appears after 8 minutes and increases by 30 minutes in the region of the central electrodes under model conditions. The measurements were carried out on two biosensor chip formats having almost identical electrophysical parameters of capacitance and conductivity at frequencies from 100 Hz to 1 MHz. It is determined that the amplitude-frequency mode and biosensor chip format can be used to develop methodological support for the identification of bacterial species, but only by optical methods. It is shown that in order to increase the number of bacteria on both of the central electrode in the concentration mode, it is necessary to increase the speed of the electroosmotic flow at alternating current, by optimizing the composition of the medium and the parameters of the electrical regime in order to equalize the rates of separation and concentration processes.

A study of the influence of the formation regimes of avalanche LEDs based on nanostructured silicon on the parameters of the formed devices, such as the light emission voltage and the stability of operation has been performed. These parameters are an important factor for the practical use of avalanche LEDs in the development of silicon photonics products, the progress of which is associated with the future of integrated electronics. For the first time, the technological operation of local through electrochemical anodizing of aluminum in various electrolytes for the formation of a separating dielectric of Schottky contacts is presented. The influence of the built-in electric charge in the separation dielectric of silicon avalanche LEDs on their current-voltage characteristics is studied. It was found that the built-in negative electric charge increases the breakdown voltage of the Schottky contact, which results in an increase of the light emission efficiency of the diode structures. An explanation of this effect is presented on the basis that the built-in negative electric charge inside the anode oxide also creates a space charge region in silicon, which helps to reduce the effect of the concentration of field lines at the edges of diode structures, performing the function of protecting the Schottky contact from edge effects as well as protective areas do. It has been established that the highest avalanche breakdown voltage is observed in diode structures with anodic oxide formed in an electrolyte based on an aqueous solution of phosphoric acid. An analysis of the characteristics of LEDs at different temperatures of silicon substrates showed an increase of breakdown voltage with increasing temperature, which is typical for avalanche breakdown during impact ionization. Stable light emission of the formed LEDs was demonstrated in a wide range of operating voltages (8–16 V). The use of silicon avalanche LEDs both as discrete devices and in integrated electronics in general has been discussed.