MOVING HEAT BLOCKS FOR AMPLIFICATION OF NUCLEIC ACIDS
20190111435 ยท 2019-04-18
Assignee
Inventors
Cpc classification
B01L2200/06
PERFORMING OPERATIONS; TRANSPORTING
B01L7/02
PERFORMING OPERATIONS; TRANSPORTING
B01L2300/0627
PERFORMING OPERATIONS; TRANSPORTING
B01L3/5027
PERFORMING OPERATIONS; TRANSPORTING
B01L2200/025
PERFORMING OPERATIONS; TRANSPORTING
B01L9/06
PERFORMING OPERATIONS; TRANSPORTING
B01L2200/141
PERFORMING OPERATIONS; TRANSPORTING
B01L7/52
PERFORMING OPERATIONS; TRANSPORTING
B01L2300/12
PERFORMING OPERATIONS; TRANSPORTING
C12Q1/6848
CHEMISTRY; METALLURGY
B01L2300/1805
PERFORMING OPERATIONS; TRANSPORTING
B01L2300/1894
PERFORMING OPERATIONS; TRANSPORTING
B01F31/20
PERFORMING OPERATIONS; TRANSPORTING
B01L2300/0829
PERFORMING OPERATIONS; TRANSPORTING
B01L2300/0618
PERFORMING OPERATIONS; TRANSPORTING
B01L2200/147
PERFORMING OPERATIONS; TRANSPORTING
B01L2200/14
PERFORMING OPERATIONS; TRANSPORTING
B01L9/065
PERFORMING OPERATIONS; TRANSPORTING
B01L2300/0816
PERFORMING OPERATIONS; TRANSPORTING
International classification
Abstract
An apparatus for thermally processing reaction material containing nucleic acid is provided. A reaction material is contained in reactors. The apparatus includes a reactor holder for statically holding the reactors; at least two heating means each being maintainable at a user specifiable temperature; and a transport means for positioning the heating means to make a contact with the reactors one at a time for specified duration. The positioning is conductable once or over a plurality of times for thermally processing the reactors between a plurality of temperatures.
Claims
1. An apparatus for thermally processing a reaction material containing nucleic acid, the reaction material being contained in a reactor and the reactor being in a form of a tube, a wellplate, a chip, or a cartridge, the apparatus comprising: a reactor holder for statically holding the reactor; at least two heating blocks each being maintainable at a user specifiable temperature; and a transport means for positioning the at least two heating blocks to make a contact with the reactor one at a time for a specified duration, wherein the positioning is conductable once or over a plurality of times for thermally processing the reactor between a plurality of the user specifiable temperatures.
2. The apparatus according to claim 1, wherein the transport means provides a linear displacement for the at leak two heating blocks.
3. The apparatus according to claim 2, wherein the transport means further provides a rotational movement for moving the at leak two heating blocks in a circular path, and the rotational movement is about a common axis for the at least two heating blocks.
4. The apparatus according to claim 3, wherein the circular path is in a vertical plane.
5. The apparatus according to claim 3, wherein the circular path is in a horizontal plane.
6. The apparatus according to claim 1, wherein the contact is made when the reactor gets inserted into a plurality of cavities in at least one of the heating blocks, a shape of the plurality of cavities is substantially conformal with at least a lower portion of the reactor.
7. The apparatus according to claim 1, wherein the at least two heating blocks comprise a thermally conductive elastomeric material.
8. The apparatus according to claim 7, wherein the thermally conductive elastomeric material is silicone or rubber.
9. The apparatus according to claim 1, wherein the at least two heating blocks each comprises a porous metal wherein a plurality of voids of the porous metal are filled by a thermally conductive liquid.
10. The apparatus according to claim 6, wherein the at least two heating blocks each comprises: a first portion coupled to the transport means; and a second portion removably coupled to the first portion, wherein the second portion accommodates the plurality of cavities.
11. The apparatus according to claim 6, wherein the at least two heating blocks each comprises: at least one injector means, wherein the injector means provides a pressure on the reactor to release the contact in an operation, before the reactor separates out of the at least two heating blocks.
12. The apparatus according to claim 11, wherein the injector means accesses the reactor via a through hole in each of the at least two heating blocks.
13. The apparatus according to claim 1, wherein at least one of the at least two heating blocks is a solid metallic block.
14. The apparatus according to claim 1, wherein at least one of the at least two heating blocks is a hollow metallic block capable of accommodating a heating medium.
15. The apparatus according to claim 1, further comprising: a fluorescence imaging means, wherein the fluorescence imaging means allows light to access the nucleic acid when the reactor is in contact with any one of the at least two heating blocks or is in air outside the at least two heating blocks.
16. The apparatus according to claim 1, wherein at least a portion of at least one of the at least two heating blocks is transparent to light for a fluorescent imaging of the reaction material while the reactor is in the contact with the at least one of the at least two heating blocks.
17. The apparatus according to claim 16, wherein each one of the at least two heating blocks is at least partially made of a transparent material that is in contact with a transparent electrical conductive layer for enabling a resistive heating.
18. The apparatus according to claim 1 comprising a temperature sensor means or a time sensor means to determine the specified duration.
19. The apparatus according to claim 18, wherein the temperature sensor means is located to sense a real-time temperature in a sample reactor containing the reaction material.
20. The apparatus according to claim 18 further comprising a calibration means for a user to calibrate the time sensor means.
21. The apparatus according to claim 1, wherein the at least two heating blocks each comprises: a first heating block, wherein the reactor is allowed to attain a predetermined high target temperature T.sub.HT in the first heating block, the predetermined high target temperature T.sub.HT is in a region of 85-99 degree Celsius for a denaturation of the nucleic acid; and a second heating block, wherein the reactor is allowed to attain a predetermined low target temperature T.sub.LT in the second heating block, the predetermined low target temperature T.sub.LT is in a region of 45-75 degree Celsius for annealing of primers or probes onto the nucleic acid or for a primer extension; wherein, the first and the second heating blocks are for a thermal cycling of the reactor to attain a polymerase chain reaction (PCR) amplification or primer extension.
22. The apparatus according to claim 1, wherein the reactor is allowed to thermally stabilize in any one of the at least two heating blocks.
23. The apparatus according to claim 1, wherein at least one of the at least two heating blocks is capable of providing temperatures with programmable ramp up or ramp down characteristics.
24. The apparatus according to claim 1, wherein the apparatus is configured to provide the user specifiable temperatures at T.sub.H and T.sub.L such that in the specified duration the reactor alternately attains: a predetermined high target temperature T.sub.HT, and a predetermined low target temperature T.sub.LT, while the apparatus adapts to a temperature-offset feature defined by at least one condition selected from the group consisting of: a) the T.sub.HT is lower than the T.sub.H, and b) the T.sub.LT is higher than the T.sub.L.
25. The apparatus according to claim 24, wherein at least one condition is selectable from the group consisting of: a) the T.sub.H is above 100 degrees Celsius, and b) the T.sub.L is lower than a room temperature.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] In the following drawings, same reference numbers generally refer to the same parts throughout. The drawings are not to scale, instead the emphasis is on describing the concept.
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DETAILED DESCRIPTION OF THE EMBODIMENTS
[0036] The following description presents several preferred embodiments of the present invention in sufficient detail such that those skilled in the art can make and use the invention.
[0037] According to a first embodiment 100,
[0038] According to a second embodiment 200,
[0039] As in
[0040] According to a third embodiment 300,
[0041] As in
[0042] According to a fourth embodiment 400,
[0043] According to a fifth embodiment 500,
[0044] As in
[0045] The above heating block temperatures T.sub.H, T.sub.L, T.sub.M and the target temperatures T.sub.HT, T.sub.LT, T.sub.MT may take other suitable values. The above thermal cycling step involving heating block 12 is optional, i:e once the reactor 5 separates from the heating block 10, the heating block 14 moves in.
[0046]
[0047] The reactors 5 in the tube form as shown could be made up of glass or metal or plastic. While making the contact with the heating blocks 10, 12, 14, 16, 18, 20, the plastic deforms to some extent to fit into the cavities 15. Thus the size of the cavities 15 may be slightly smaller than those of the reactors 5 to ensure a tight fit for a good contact with the cavities 15. However since the glass or metallic ones do not deform, slight oversize of the cavities 15 need to be used thereby forming a gap 34 as shown in
[0048]
[0049] According to an embodiment as shown at
[0050] As show in
[0051] It will be understood by those skilled in the art that in the preceding embodiments, the shape of the cavities 15 may preferably be substantially conformal with the lower portions of the reactors 5 such that tight and uniform contact of the reactor(s) 5 with the heating blocks 10, 12, 14, 16, 18, 20 may be established for speedy heat exchange. This is desirable both for the quality control of the thermal processing and for reducing the cycle time. The pitch of the cavities 15 in the heating blocks 10, 12, 14, 16, 18, 20 need to match the pitch of the reactors 5 whether as individual reactors 5 held by the reactor holder 4 or in the form of well plates. During the thermal processing, the positioning of the heating blocks 10, 12, 14, 16, 18, 20 under the reactors 5 needs to be executed with the required precision. Temperature sensors (not shown) are provided with each heating block to monitor and regulate the specified temperature. The temperatures of the different heating blocks 10, 12, 14, 16, 18, 20 may co-relate to the target temperatures for the thermal processing such as for DNA denaturation, annealing and extension. For temperature control in the thermal cycling process, the temperature sensor may be mounted inside each heating block or mounted inside a reactor 5 dedicated for temperature sensing which has a similar heat transfer characteristics as the reactor 5 containing the reaction material. Such a reactor 5 with the temperature sensor is inserted into the cavity of the different heating blocks together with the other reactors 5.
[0052] The apparatus may be programmed such that the duration of the contact is dependent on a target temperature to be achieved by the reactor(s) when in the contact. The temperature of any of the heating blocks 10, 12, 14, 16, 18, 20 may be set to be higher than the target temperature to speed up the rate of heating of the reactor(s). Similarly the temperature of any of the heating blocks 10, 12, 14, 16, 18, 20 may be set to be lower than the target temperature to speed up the rate of cooling of the reactor(s). In order to enhance the rate of heating for the reactor 5, the user specifiable temperature in one or more of the heating block(s) 10, 12, 14, 16, 18, 20 may be maintained higher than the target temperature such as the denaturation temperature for the reactor 5. The reactor 5 can remain in the heating block(s) 10, 12, 14, 16, 18, 20 for a specified period of time required for denaturation. Similarly In order to enhance the rate of cooling for the reactor 5, the user specifiable temperature may be maintained lower than the target temperature such as the annealing or extension temperature. The reactor 5 can remain in the heating block(s) 10, 12, 14, 16, 18, 20 for another specified period of time as required for annealing and extension for the reactor 5. For such cases it is preferable to have the tube mounted with a temperature sensor insider the tube. When the temperature sensor inside the reactor 5 senses the temperature reaching the target temperature, the rotary motion stage 22 and the linear motion stage 24 would separate the heating block from the reactor 5 and bring in another heating block to contact the reactor 5. The preceding embodiments show the reactors 5 in the form of tubes and the heating blocks 10, 12, 14, 16, 18, 20 to be provided with cavities 15 to receive the lower side of the reactors 5 when in the active position. However, this is not a limitation. Reactors 5 with other shapes including PCR chips and cartridges may also be used. The PCR chip requires multilayer bonding or glue sealing of plates or films which may frequently cause delamination and leaking during the thermal cycling process. The cartridges have similar problems as well. The conventional PCR tubes and wellplates are molded as a single piece plastic without any bonding required. This provides a more reliable vehicle to contain the biological sample and reagent before, during and after the nucleic acid analyses. Moreover, the PCR chip has a flat surface to be in contact with the heating blocks 10, 12, 14, 16, 18, 20 and such one-sided heating and cooling could generate a thermal gradient across the PCR chip thereby making the temperature inside inaccurate and the temperature control difficult. On the contrary, as described in the preceding embodiments, the reactors 5 in the form of conventional PCR tube or a tube on a PCR wellplate are inserted into the cavities 15 for heating and cooling, and such cavities 15 surround the tube in all directions making the heating and cooling uniform over the domain of the reaction material in the tube. This helps the temperature field to be more uniform inside the reaction material during the thermal cycling.
[0053] The materials used to construct the reactors 5 may be plastics, elastomer, glass, metal, ceramic and their combinations, in which the plastics include polypropylene and polycarbonate. The glass reactor 5 can be made in a form of a glass capillary of small diameters such as 0.1 mm-3 mm OD and 0.02 mm-2 mm ID, and the metal can be aluminum in form of thin film, thin cavity, and capillary. Reactor materials can be made from non-biological active substances with chemical or biological stability. At least a portion of the reactor 15 is preferred to be transparent. The volume of the at least one reactor 5 may be in the range 1 L to 500 L. Smaller the volume, faster is the heat transfer, higher is the speed of PCR, smaller are the required heating block sizes and more compact is the apparatus. The reaction material in all the reactors 5 in the reactor holder 4 may not be identical. Simultaneous PCR can be advantageously conducted for different materials if the heating block temperatures are suitable. The heating blocks may be shared between different process steps by altering the temperatures. The embodiments described above may be suitable for one reactor 5 or a plurality reactors 5. The reactor 5 may be in the form of tube(s) as shown or as wellplate(s) or chip(s) or cartridge(s) and the like.
[0054] When using the above described apparatus for nucleic acid analysis and processing, the reaction material comprises reaction constituents including at least one enzyme, nucleic acid and/or particle containing at least one nucleic acid, primers for PCR, primers for isothermal amplifications, primers for other nucleic acid amplifications and processing, dNTP, Mg.sup.2+, fluorescent dyes and probes, control DNA, control RNA, control cells, control micro-organisms, and other reagents required for nucleic acid amplification, processing, and analysis. The particle containing nucleic acid mentioned above comprises at least one cell virus, white blood cell and stromal cell, circulating tumor cell, embryo cell. One application may be to use the apparatus to test different kinds of reaction materials against the same set of primer and probes, such as test more than one sample. For such application, different kinds of reaction material containing no target primers and/or probes are each loaded into one reactor 5 in a reactor array, with all the reactors 5 being pre-loaded with the same set or the same sets of PCR primers and/or probes. For the same application, different kinds of reaction materials pre-mixed with respective PCR target primers and/or probes are each loaded into one reactor 5 in a reactor array, with all the reactors 5 being not pre-loaded with the same set of PCR primers and or probes. The reaction materials can include control genes and/or cells and corresponding fluorescent dyes or probes. In the above situations, the different probes emit light of different wavelengths. Another application of the methods and devices are used to test the same reaction material against different sets of primer and probes. One example of such an application is to test one type of sample for more than one purpose. For this application, a single reaction material is added into the reactors 5 each loaded with at least one different set PCR primers and or probes. The reaction material can include control genes and/or cells and corresponding fluorescent dyes or probes. In the above situations, the different probes emit light of different wavelengths. The above reaction material is used in polymerase chain reaction, reverse transcription-PCR, end-point PCR, ligase chain reaction, pre-amplification or target enrichment of nucleic acid sequencing or variations of polymerase chain reaction (PCR), isothermal amplification, linear amplification, library preparations for sequencing, bridge amplification used in sequencing. The variation of the polymerase chain reaction mentioned above comprises reverse transcription-PCR, real-time fluorescent quantitative polymerase chain amplification reaction and real-time fluorescent quantitative reverse transcription polymerase chain amplification reaction, inverse polymerase chain amplification reaction, anchored polymerase chain amplification reaction, asymmetric polymerase chain amplification reaction, multiplex PCR, colour complementation polymerase chain amplification reaction, immune polymerase chain amplification reaction, nested polymerase chain amplification reaction, the target enrichment of pre-amplification or nucleic acid sequencing, ELISA-PCR.
[0055] From the foregoing description it will be understood by those skilled in the art that many variations or modifications in details of design, construction and operation may be made without departing from the present invention as defined in the claims.