RU171227U1 - CAMERA FOR EXPRESS COMPLEX ELECTROKINETIC ANALYSIS - Google Patents

Abstract

The utility model relates to the field of medical technology, veterinary medicine and microbiology and can be used for biological studies of cell suspensions and subcellular formations for diagnostic and scientific purposes. The objective of the claimed utility model is to create a camera for integrated express electrokinetic analysis, which provides a comprehensive analysis of living cells by simultaneously creating conditions for electrophoresis and dielectrophoresis in one camera, which have enhanced user friendliness and improved ergonomics. The chamber for express complex electrokinetic analysis contains a glass slide holder formed by a lid and a base, in which a slide glass heater is located, wherein a standard size slide with electrodes for electrophoresis and dielectrophoresis and a cover glass are used as a slide; mounted on top of these electrodes, the slide holder is compact and has a special groove for placement it slide, and on the edges of the two recesses are formed holder for the operator's finger, providing convenience and reliability of the slide placement in said holder.

Description

The utility model relates to the field of medical technology, veterinary medicine and microbiology and can be used for biological studies of cell suspensions and subcellular formations for diagnostic and scientific purposes.

A device for microelectrophoresis of blood cells and epithelial cells (RF patent No. 2168176, IPC G01N 33/49, publ. 05.27.2001), containing a chamber with electrodes, a thermostat, a power source and a control unit, while pairs of electrodes are additionally introduced into it and it is provided with a generator unit and a switch unit for creating an 8-vector electric field.

According to the specified analogue, the studied objects are placed in an incubation medium in an alternating, multi-vector and symmetric electric field, bioelectric parameters are estimated by changing the positions of the cells, as well as their shells and nuclei.

The disadvantage of this camera is the limited and one-sidedness of the information received, since the data on electrophoretic mobility allow us to determine only the electrical properties of cells and only partially - biological.

Also known is a chamber for microelectrophoresis (RF patent No. 2271734, IPC AB 5/00, G01N 2728, publ. March 20, 2006), containing a retractable platform with electrodes located on it and a cover glass placed on them, which is located separated from the platform. The camera also has a temperature sensor and a resistive heating layer located below the coverslip.

The chamber is filled with the preparation of the analyzed cells in a buffer solution, when the voltage is turned on, an alternating homogeneous field is created between the electrodes, under the influence of which charged living cells perform reciprocating motion with different amplitudes proportional to their integral charges (the process of microelectrophoresis is carried out). The electrical and biological parameters of the cells (their average integral charge and membrane potential, the histogram of the cells by charges and the proportion of mobile cells relative to their total number) are calculated from the determined characteristics of the behavior of the cells and the known indicators of the fields and environment.

The disadvantage of this camera is that when it is used, it is possible to conduct only one-sided analysis of the studied object, based on the calculation of only the electrical properties of cells in a low-frequency (0.3-1.0 Hz) field. In addition, due to the relatively large distance between the electrodes of the chamber, in order to provide the necessary field strength, a voltage of about 25-30 V is applied to them, which, with a used electrode thickness of 20-50 μm, initiates a sufficiently high current density flowing through the buffer solution. For a number of ordinary buffer solutions in a low-frequency field, this leads to a noticeable electrolysis, the products of which gradually change the pH of the solution, affect the nature of the movement of cells and eventually lead to destruction of the electrodes.

The closest analogue, taken as a prototype, is a device for the complex analysis of parameters of living cells (RF patent No. 2357251, IPC G01N 33/487, published July 20, 2007), containing a detachable housing, a retractable platform with electrodes located on it and a cover glass, a temperature sensor and a pad with a resistive heating layer.

In this chamber, one group of electrodes is intended for electrophoresis, and the other for dielectrophoresis. First, a voltage with a low frequency (0.25-1 Hz) is applied to a group of electrodes intended for electrophoresis and the characteristics of the movement of living cells under the influence of a uniform low-frequency field are recorded. Then, a voltage from a medium and high frequency generator (10 kHz-20 MHz) is applied to a group of electrodes intended for dielectrophoresis and the characteristics of the movement of living cells under the influence of an inhomogeneous field of medium and high frequencies are recorded.

The disadvantage of this prototype is the use of a custom glass slide, which complicates the replication and use of the device. Microscopic observations are complicated by the fact that the slide does not have a distinct division into zones in which electrophoresis and dielectrophoresis are performed, which can affect the accuracy of the results and the duration of the analysis.

The objective of the claimed utility model is to create a chamber for rapid complex electrokinetic analysis, providing a comprehensive analysis of living cells by simultaneously creating in one chamber conditions for electrophoresis and dielectrophoresis, which has enhanced user friendliness and improved ergonomics.

The technical result of the utility model is to increase the convenience and reliability of placing a glass slide in the holder to perform cell analysis with increased information content.

The specified technical result is ensured by the fact that the camera for rapid complex electrokinetic analysis contains a glass slide holder formed by a lid and a base in which the slide glass heater is located, while a slide of a standard microscopy size with electrodes placed on its upper surface is used as a slide for electrophoresis and dielectrophoresis, as well as a cover slip mounted on top

these electrodes, and the slide holder corresponds to the standard size of the glass for microscopy and has a groove for placing the slide in it, and two notches for the operator’s fingers are made along the edges of the holder.

A standard glass slide has a size of 76 × 26 × (1-1.5) mm.

The claimed device is illustrated by the drawings shown in FIG. 1-3.

In FIG. 1 shows a holder representing a general view of a camera assembly without a glass slide.

In FIG. 2 shows a general view of a glass slide.

In FIG. 3 shows a view of the camera holder in an inverted state with a transparent base.

The camera is by design a detachable device, the main parts of which are shown separately in FIG. 1 and FIG. 2. The glass slide holder (Fig. 1) includes a cover 1 and a base 2, in which a glass slide heater 3 is also placed, and between the lid 1 and the base 2 are placed (Fig. 3) conductors 4 that supply power to the heater 3 and the electrodes of the slide glass (Fig. 2) from the connector 5 of the camera (Fig. 3).

The heating element in the heater 3 is deposited on an optical quality glass, which provides free light access from below to the cell preparation placed on a glass slide (Fig. 2) above the heater 3, to ensure microscopic observations.

The holder (Fig. 1) is equipped with a special groove 6 for placing a slide in it, while the base 2 has two special recesses 7 for convenient placement of the glass (these include the ends of the fingers of the operator when inserting the slide completely).

A glass slide (Fig. 2) was made using a standard microscope slide by placing electrodes 8 of

electrically conductive material for cellular microelectrophoresis and electrodes 9 for dielectrophoresis.

The voltage to the electrodes 8 is supplied through the contact pads 10 and the elastic contacts 11 of the holder (Fig. 3), the voltage to the electrodes 9 (Fig. 2) is supplied through the pads 12 and the elastic contacts 13 of the holder (Fig. 3), to the contacts 11 themselves and 13 voltage is supplied by conductors 4 from connector 5.

In addition, on the glass slide (Fig. 2) there are support pads 14 for supporting the coverslip for microscopes (not shown in the figures) in the event that the electrodes 8 and 9 have different thicknesses - this is required to ensure a uniform thickness across the gap between subject and cover glasses in which the cellular preparation is located. The temperature sensor 15 is also placed in the slide, the conclusions of which are connected through the pads 16 and the conductors 4 (Fig. 3) to the connector 5.

At the base of the camera holder (Fig. 3) there are openings 17 for unhindered passage of light from below through the glass of heater 3 to a cell preparation placed on a glass slide (Fig. 2) above heater 3 (Figs. 1 and 3) to provide microscopic observations. On the underside of the slide, rings 18 are made of opaque material that limit the working areas of microscopic observations located between the respective pairs of electrodes.

The camera for complex electrokinetic analysis works as follows.

On the glass slide (Fig. 2), inserted into the holder or located separately from it, between the electrodes 8 and 9, a necessary amount (a few drops) of the analyzed cell preparation is applied with a pipette. Then, a coverslip is placed above the electrodes (not shown in the figures), under which the previously applied drops of the drug spread and cover both pairs of electrodes and the working areas between them. A glass slide with a coverslip and a cell preparation between them are inserted into the groove 6 (Fig. 1)

holder (if it was not placed in the groove from the very beginning), then the camera is mounted on the microscope stage so that under the lens there is a working area of microelectrophoresis. A cable from the voltage generator is connected to connector 5 (Fig. 3), and after voltage is applied, the behavior of cells in an electric field is analyzed under a microscope using the microelectrophoresis technique, and then the dielectrophoresis technique after the camera is moved by feeding a stage to move the dielectrophoresis working area under the lens a microscope.

If it is necessary to perform the analysis at temperatures of the cell preparation above room temperature, the analysis working area is preheated using heater 3 (Figs. 1 and 3) before starting the study for several minutes. The actual temperature of the drug is determined by the readings of the temperature sensor 15 in contact with it (Fig. 2), which also provides a regime of thermal stabilization of the drug’s temperature.

Claims (8)

1. Camera for rapid complex electrokinetic analysis containing a slide holder formed by a lid and a base, in which a slide slide heater is located, characterized in that the slide is a microscope-sized slide with electrophoresis electrodes placed on its upper surface and dielectrophoresis, as well as a coverslip mounted on top of said electrodes, wherein the glass slide holder corresponds to one hundred the standard size of the glass for microscopy and has a groove for placing a slide in it, and two notches for the operator’s fingers are made along the edges of the holder. 2. The camera according to claim 1, characterized in that the glass slide has a size of 76 × 26 × 1.5 mm. 3. The chamber according to claim 1, characterized in that the electrodes for microelectrophoresis and electrodes for dielectrophoresis have different thicknesses. 4. The camera according to p. 3, characterized in that the slide has a reference area for supporting the coverslip. 5. The camera according to claim 1, characterized in that the slide has a thermal sensor. 6. The camera according to claim 1, characterized in that in the base of the camera holder there are two openings for unhindered passage of light from below through the glass of the heater. 7. The camera according to claim 1, characterized in that on the underside of the glass slide are applied rings of opaque material that limit the working areas of microscopic observations. 8. The chamber according to claim 7, characterized in that said opaque rings are located between the respective pairs of electrodes.

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