A DEVICE FOR CONDUCTING BIOLOGICAL AMPLIFICATION REACTIONS

Abstract

The object of the invention is a device for conducting amplification reaction of biological samples with a system for independent control of the temperature of test tubes in a heating assembly comprising a multipart heating slot located in the cooling system housing, characterised in that the heating assembly comprises at least one heating slot (100) comprising a metal heating sleeve (101) wound around with a bifilar winding wire made of enamelled winding wire (102), which is covered with a composite polymer layer (103), wherein a temperature sensor (104) is located on the surface of the winding wire, and at least one heating slot is mounted on the PCB control board (105) located on the cooling system housing (112),

Claims

1. Device for conducting amplification reaction of biological samples with a system for independent control of the temperature of test tubes in a heating assembly comprising a multipart heating slot located in the cooling system housing, a control system, and a power supply system, characterised in that the heating assembly comprises at least one heating slot (100) comprising a metal heating sleeve (101) wound around with a bifilar winding wire made of enamelled winding wire (102), which is covered with a composite polymer layer (103), wherein a temperature sensor (104) is located on the surface of the winding wire, and at least one heating slot is mounted on the PCB control board (105) located on the cooling system housing (112).

2. The device according to claims 1 to 2, characterised in that the cooling system housing (112) comprises at least one fan (117) connected at the outlet to a least one housing (112) of the air duct (114) for placing the PCB board (105) with at least one heating slot (100).

3. The device according to claims 1 to 2, characterised in that the housing (112) comprises two side walls (120) connected with each other by means of a third wall (115, 121).

4. The device according to claims 1 to 3, characterised in that the temperature ramp of the heating sleeve is at least 20° C./s.

5. The device according to claims 1 to 4, characterised in that the temperature sensor (104) is a Pt100 or Pt1000 sensor.

6. The device according to claims 1 to 5, characterised in that the PCB board (105) is connected to the control system and to the power supply.

7. The device according to claims 1 to 6, characterised in that the cross-section of the heating slot (100) is circular.

8. The device according to claims 1 to 7 characterised in that the longitudinal cross-section of the heating slot (100) has a tapered cone shape.

9. The device according to claims 1 to 8, characterised in that the thickness of the heating sleeve (101) does not exceed 0.1 mm.

10. The device according to claims 1 to 9, characterised in that the heating sleeve (101) is made of copper.

11. The device according to claims 1 to 10, characterised in that the winding wire (102) is made of copper.

12. The device according to claims 1 to 11, characterised in that the winding wire (102) is enamelled with a polyurethane based enamel.

13. The device according to claims 1 to 12, characterised in that the PCB board (105) comprises a slit (106) reducing the heat transfer to the PCB board (105) from the heating slot (100).

14. The device according to claims 1 to 13, characterised in that an inner chamber (118) comprising the excitation and fluorescence measurement arrangement (108, 109, 110, 111) is located in the housing (112) of the air duct (114).

15. The device according to claims 1 to 14, characterised in that the excitation and fluorescence measurement arrangement is mounted on the housing (112) of the air duct (114) and comprises: an optic fibre (108) of the fluorescence excitation diode connected to the diode (109) for fluorescence excitation, an optic fibre (110) with a filter for the fluorescence detector connected to the fluorescence detector (111), wherein the excitation and fluorescence measurement arrangement is separated from the air duct (114) with an insulating surface (115), through which optic fibres of the excitation (108) and fluorescence measurement (110) arrangement are introduced.

16. The device according to claims 1 to 15, characterised in that the excitation and fluorescence measurement arrangement is connected to the heating slot by means of optic fibres (108, 110).

Description

EXAMPLE 1

Device Structure without the Optical System According to the Invention

[0032] The device is constructed of a three-piece housing, which is comprised of a fan 117 connected at the outlet to the housing 112 having one side open on the inside, in which, due to such a design, a U-shaped channel is formed, and a PCB board 105 with heating slots 100. The housing 112, which is shown in FIG. 5 and FIG. 7, is open on one side. This allows mounting the PCB board 105 with heating slots 100 in the device. The PCB board 105 is mounted to the housing of the walls 120 of the housing 112 by means of fastening openings (FIG. 5). And after placing it, a U-shaped air duct is closed and an air duct 114 is formed. The heating slots 100 are made of a number of layers. The heating slot 100 base is constituted by a heating sleeve 101 made of metal with high heat conductivity, e.g. copper formed in a shape corresponding to the shape of the reaction test tube, e.g. cone. Further, on the sleeve 101, a tightly wound winding wire 102 is present, FIG. 3, having a bifilar winding (FIG. 2) and the winding wire 102 has been additionally coated with a polymer composite layer 103 (FIG. 4). On the surface, formed by the bifilarly wound winding wire 102, a Pt100 or Pt1000 temperature sensor is located and only on top of it the polymer composite 103 is deposited. Such structure provides direct temperature reading and at the same time provides mechanical mounting and protection from the influence of outside conditions. The heating slot 100 is mounted to the PCB board 105 by means of a lead-free solder. Whereas on the PCB board 105, additional openings 106 are present, in order to limit the heat transfer from the slot 100 to the board 105. The board 105 is connected to the control system and the current supply.

[0033] The slot structure described above and illustrated in FIGS. 1 to 4 solves the technical problem. It provides precise control of the heating slot temperature. Moreover, through it, it is possible to power the heating slot independently, and therefore to independently control the temperature of the test tube inserted therein. Placing the heating slot or a slot assembly in the cooling channel provides rapid cooling. The independent control of the current controlling the heating of the sleeve results in low requirement for heating power for a single test tube, which is shown in FIG. 10. Additionally, the above structure is characterised by low mass, and a minimal heat capacity associated with it, as well as a low manufacturing cost. It results also in that, through it, a rapid temperature ramp is achieved.

EXAMPLE 2

Device Structure with the Optical System (FIG. 7)

[0034] The structure of this variant of the device is based on the design of example 1. A significant difference is comprised in the structure of the housing 112 of the air duct 114.

[0035] The housing 112 comprises an additional inner chamber 118, separated from the air duct with an insulating partition 115. The chamber 118 comprises an excitation and fluorescence measurement assembly comprised of the following elements: a fluorescence excitation diode optic fibre 108, a fluorescence excitation diode 109, optic fibre 110 with a filter for the fluorescence detector, fluorescence detector 111. The optic fibres are led from the chamber 118 to the channel 114 and are mounted on the bottom of the heating slot 100.

[0036] The embodiment according to the present invention has all the advantages of the solution shown in Example 1.

EXAMPLE 3

Determining the Temperature Parameters of the Device for a Single Heating Slot

[0037] On a station with a FLIR A40M thermal imaging camera, the temperature ramp time for an analog regulator power with 5V DC voltage was measured. The average current at the time of heating was 1.5 A, which results in power about 7.5 Watt. The function of temperature ramp in time is shown on the graph in FIG. 8. A linear approximation of the measured curve was performed and a linear relation of the temperature ramp over time having a ramp coefficient higher than 21° C. per second was obtained. After 3 seconds, an attempt to stabilise the temperature at the level of 77° C. takes place. The regulator does not comprise an ID member and was designed only for temperature ramp testing. In case of digital signal processing, a very good temperature stabilisation and lack of overregulation should be expected. Both the curve section after reaching maximum and its slope indicate a very rapid cooling of the heater even in case if an additional air cooling is not present.

[0038] The results were obtained using an analog temperature regulator having a diagram shown in FIG. 12.

EXAMPLE 4

Determining the Power Consumption Parameters for a Single Heating Slot According to the First Example

[0039] The temperature measurement was conducted by means of a FLIR A40M thermal imaging camera. The energy requirement can be determined from the graph in FIG. 10. The graph shows that the power of 0.7 W is sufficient to maintain the temperature in a test tube having a 200 μl volume on 100° C. level. (0.35 A×2V).