THERMAL CYCLING DEVICE
Multi-layer devices suitable for thermal cycling processes. The devices are particularly suitable for performing polymerase chain reactions (PCR). One embodiment includes a first conducting layer, a second conducting layer adjacent to the first layer, and a third conducting layer adjacent to the second layer opposite the first layer. Insulating layers are positioned between said three conducting layers. Continuous channels are formed within the layers. The channels can be formed in either the conducting layer or the insulating layers, or both. Other embodiments include two conducting layers. At least one integral or separate temperature source may be provided to maintain the conducting layers at various desired temperatures.
The present application is a continuation of U.S. patent application Ser. No. 11/744,676 filed on May 4, 2007, which is a continuation-in-part of U.S. patent application Ser. No. 10/906,546, filed on Feb. 24, 2005. The present invention also claims priority to U.S. provisional applications 60/547,036, filed Feb. 24, 2004, 60/629,910, filed Nov. 22, 2004, and 60/745,550, filed May 5, 2006, the disclosures of which are incorporated by reference herein.
TECHNICAL FIELDThe present invention relates generally to a thermal cycling devices, and more specifically, to a multi-layer thermal cycling devices suitable for the life science, medical devices and biotechnology fields. One suitable application is to perform a polymerase chain reaction (PCR).
BACKGROUNDVarious fields such as life science, medical devices and biotechnology often require thermal cycling for performing various reactions. One type of reaction is the polymerase chain reaction (PCR) in which a biological sample such as a DNA fragment is replicated.
PCR has been the preferred method for replicating, or “amplifying” specific and singular nucleic acid constituents in an otherwise complex sample. Among the requirements of the PCR protocol is that the PCR sample, consisting of the biologic sample and PCR reagents, be exposed to three distinct temperatures for a specific length of time. The temperature and time of the exposure is optimized for the particular nucleic acid sequence desired. It is also a requirement that the PCR sample be exposed to the three temperatures multiple times. In the scientific vernacular, these two requirements are commonly referred to as thermal cycling.
Scientific endeavors such as the Human Genome Project and other similar efforts require that an extraordinary number of PCR reactions be conducted. The costs and time associated with the performance of PCR can become prohibitive for scientific studies that require thousands or even millions of PCR reactions. Cost reduction can be realized by reducing the volumes of the materials required for a successful PCR reaction through miniaturization. Total PCR reaction time can be reduced by decreasing the time required for the sample to be exposed to, and equilibrate at each of the temperature set points in the prescribed PCR protocol.
Current art has relied on various means to achieve these goals. Each method and device contains one or more of the following attributes that prohibits rapid temperature changes in the PCR sample. The temperature of one or more sources of thermal energy must be changed to establish each temperature set point. The time required for this is determined by thermal conductivity of the device material which is inherently slower than the PCR sample itself. If constant temperature thermal sources are employed, regional areas of the device equilibrate at the desired temperature set points but gradual temperature changes are established in the surrounding areas within the device due to the thermal conductivity properties of the materials. This results in a slow thermal transition of the sample as it moves through the device. The time to traverse these transition temperature ranges serves to increase the total reaction time in comparison to methods that offer abrupt or instantaneous changes. It also requires that the device be larger and therefore does not provide the highest degree of miniaturization. Thus, the full cost benefit from reduced PCR sample volumes is not realized.
There is substantial development of devices and methods to facilitate the temperature cycling, also referred to as thermal cycling. U.S. Pat. No. 6,337,435 TEMPERATURE CONTROL FOR MULTI-VESSEL REACTION APPARATUS by Daniel Chu, et al. describes an approach whereby a sample or samples in a multi-well container are subjected to temperature changes caused by physical contact between the multi-well container and a heating device. The time required to perform the thermal cycling is largely determined by thermal mass and other physical properties of the heating device and is therefore relatively slow.
The multi-well device is usually opened at the top to provide access to the wells for the introduction and removal of the sample. This creates an environment for the undesirable evaporation of the sample. The aforementioned patent, as well as others, strive to reduce this effect by implementing covers. The covers reduce evaporation but present an opportunity for undesirable condensation. This effect is often mitigated by heating the cover but this then introduces a competing temperature source to the system, further increasing the total PCR reaction time.
There has been a significant effort within the biotechnology community to create closed miniaturized devices in order to mitigate the disadvantages of the open well/vessel systems. The advantages of a closed miniaturized system would be to reduce sample evaporation, reduce condensation, and to reduce costs by using smaller sample and reagent volumes. Exemplary of such miniaturized systems is U.S. Pat. No. 6,284,525 MINIATURE REACTION CHAMBER AND DEVICES INCORPORATING SAME by Richard Mathies and Adam Woolley and U.S. Pat. No. 6,261,431 PROCESS FOR MICROFABRICATION OF AN INTEGRATED PCR-CE DEVICE AND PRODUCTS PRODUCED BY THE SAME by Richard Mathies, Peter Simpson, and Stephen Williams. Such devices are fabricated containing closed reaction chambers. Sample and reagent liquids flow into and out of these chambers through a network of fluid channels. Heating elements such as resistive wire elements are fabricated within these chambers and provide the heating energy required to execute the PCR assay.
As with the larger and open system, the thermal properties of the device and the structural design primarily determine the reaction time. Although these systems are an improvement over the previously described approach, the thermal characteristics of such a structure is a limiting factor. Also, fabricating, controlling, and monitoring of the in situ heating elements is complicated and adds appreciably to the cost of the device.
Another method that attempts to accelerate the PCR process is described in U.S. Pat. No. 6,180,372 METHOD AND DEVICES FOR EXTREMELY FAST DNA REPLICATION BY POLYMERASE CHAIN REACTIONS (PCR) by Jochen Fanzen. In this embodiment, a two dimensional network of microfluidic channels is contained within two temperature heating/cooling elements. The microchannel device is exposed to rapid temperature changes by changes in the heating/cooling elements above and below the device. This system is very efficient in the energy transfer between the heating/cooling elements due to complete physical contact with the elements. However, the total PCR reaction time is still limited by the ability to change temperature within the heating/elements and within the microchannel material.
The above-mentioned devices and methods address the issue of thermal cycling for PCR by various configurations of heating elements in an attempt optimize the energy transfer from the elements to the device and eventually the PCR sample contained there in. All of these methods and devices are limited by their ability to transfer thermal energy through the device and into the sample. Further limitations are present when the heating elements themselves must also change temperature in order to expose the PCR sample to each desired temperature set point in the PCR protocol.
It is therefore desirable to provide a thermal cycling device that reduces the thermal limitations of prior known devices as well as reducing evaporation, condensation and cost so that a device for rapidly performing thermal cycling is provided.
SUMMARYThe present invention provides a method and apparatus for improved thermal cycling performance.
In one aspect of the invention, an apparatus includes a first layer, a second layer proximate to the first layer, a third layer proximate to the second layer opposite the first layer, and a continuous channel. The continuous channel is formed within the first layer, second layer and third layer. The continuous channel has a plurality of cycle segments. Each of the cycle segments comprises a first portion disposed within the first layer, a second portion disposed within the second layer, and a third portion disposed within the third layer.
In a further aspect of the invention, a device for performing a reaction comprises a first heating means, a first thermally conductive layer thermally coupled to the first heating means, a first insulating layer proximate the first thermally conductive layer, a second thermally conductive layer directly adjacent to the first insulating layer and a second insulating layer directly adjacent to the second thermally conductive layer. A third thermally conductive layer is disposed proximate to the second layer opposite the first layer. A continuous channel is formed through the first thermally conductive layer, the first insulating layer, the second thermally conductive layer, the second insulating layer, and the third thermally conductive layer. The continuous channel has a plurality of cycle segments, each of the cycle segments comprising a first portion disposed within the first thermally conductive layer, a second portion disposed within the third thermally conductive layer, and a third portion disposed within the second thermally conductive layer.
Additional embodiments of the invention include two and three layer devices which include the fluid channels in one or more of the insulating layers. Other embodiments include fluid flow channels which “fold back” from one-side of the device to the other in the same layer or temperature strata. Further embodiments include tabbed connectors to one or more of the thermal conductive layers in order for heating or heat sinking purposes.
In yet another aspect of the invention, a method of performing a reaction comprises introducing a sample into a device having a first layer, a second layer, and a third layer performing a first portion of a cycle in a first layer at a first temperature, moving the sample to the third layer, thereafter performing a second portion of the cycle in the third layer at a second temperature lower than the first temperature, moving the sample to the second layer, thereafter performing a third portion of a cycle in the second layer at a third temperature between the first temperature and the second temperature, and repeatedly performing the first portion, second portion and third portion for a predetermined number of cycles to perform the reaction.
Other method embodiments include two and three layer devices which move the samples through channels in one or more of the insulating layers and other devices wherein the channels “fold back” from one side of the device to the other in the same layer or temperature strata.
One advantage of the invention is that only two sources of thermal energy are required to perform a polymerase chain reaction that uses three different temperatures. Advantageously, because the upper and lower layers are maintained at a temperature, delays due to thermal cycling of the individual layers are not present. This accelerates the entire process compared to the existing art.
Other advantages and features of the present invention will become apparent when viewed in light of the detailed description of the preferred embodiment when taken in conjunction with the attached drawings and appended claims.
Various features and advantages of the present invention will become readily apparent upon reading the following detailed description upon reference to the attached drawings, in which:
In the following figures the same reference numerals will be used to identify the same components. It should be noted that various examples including reagents, time, materials, and channel configurations are set forth below by way of example and are not meant to be limiting. The present invention is also described with respect to a polymerase chain reaction (PCR). However, various biological and chemical fields may benefit by the use of the present invention. It should also be noted that although the device is suitable for thermal cycling, a heating device may not be integral to the apparatus. That is, the heating device may be an external device coupled to the apparatus.
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Insulating layers may be used to at least partially thermally isolate the various layers. A first insulator 24 is disposed between the first thermally conductive layer 18 and the second thermally conductive layer 20. A second insulator 26 is disposed between the second thermally conductive layer 20 and the third thermally conductive layer 22. The first insulator 24 and second insulator 26 may be formed as a planar layer between the thermally conductive layers. Of course, other embodiments of such an insulator would be evident to those skilled in the art. The first insulator 24 and second insulator 26 are preferably fabricated from materials with low thermal conductive properties, such as polypropylene, polycarbonate, polyethylene or polyimide. As is best shown in
Ports 28 may be formed in various manners including drilling or laser ablation. When in a layer form, the first insulator has a top surface 30 and a bottom surface 32. The top surface 30 is adjacent to the bottom surface 34 of the first conductive layer 18. The bottom surface 32 of the insulator 24 is directly adjacent to the top surface 38 of thermally conductive layer 20. The bottom surface 40 of second thermally conductive layer 20 is directly adjacent to the top surface 42 of the second insulating layer 26. The bottom surface 44 of insulator 26 is directly adjacent to the top surface 46 of third thermally conductive layer 22. The top surface 36 of first thermally conductive layer 18 has an inlet port 50 therein. Inlet port 50 may be used to provide a fluid sample to the fluidic device 12. An outlet port 52 is used to remove the fluid sample from the fluidic device 12. The layers may be coupled together using a thin layer of epoxy or other adhesive. Alignment guides or pins may be used in alignment of the device during manufacturing.
As will be further described below, various types and positions of temperature sources 14, 16 may be used. Separate devices such as platens or integral devices may be used. As is illustrated in
An outlet port 52 is illustrated through third thermally conductive layer 22. The outlet port allows the fluid sample to exit the device. A continuous channel 54 is illustrated through the device. The continuous channel may be broken into various cycles that have portions corresponding to each layer of the device. In a PCR environment, three different temperatures are desired. Exposure to three different temperatures forms one amplification cycle of the PCR reaction.
The continuous channel includes an entry portion 56, a first cycle portion 58 disposed within the first thermally conductive layer 18, and a connection portion 60 that couples the fluid sample from the first thermally conductive layer 18 to the third thermally conductive layer 22. The third thermally conductive layer 22 has a second cycle portion 62 therein and is thus exposed to a second temperature less than the first temperature of the first thermally conductive layer. The second cycle portion 62 is fluidically coupled to a second connection portion 64 that couples the fluid from the second cycle portion 62 to the third cycle portion 66. The third cycle portion 66 is disposed within the second thermally conductive layer 20. As will be described below, various numbers of cycles through the first portion 58, second portion 62, and third portion 66 may be performed depending on the various parameters and desired amplification in a PCR process. Once the predetermined number of cycles through the device is performed, the fluid sample leaves the device through the third layer 22 through an exit portion 68. Exit portion 68 is performed when the fluid passes through the desired number of cycles formed in the fluidic device 12. The lengths and cross-sectional areas of the first portion 58, second portion 62, and third portion 66 are sized so that the fluid sample in each pathway is exposed to the temperature for a predetermined amount of time. The size of the pathway may be changed by varying the cross-sectional area and the length. The dwell time is proportional to length and inversely proportional to channel cross-sectional area. The fluid inlet 50 and fluid outlet 52 may be positioned in various layers. The position may be dictated as a matter of convenience depending on the configuration of the equipment to which the fluidic device is attached.
The first temperature source 14 and second temperature source 16 may be formed of various types of materials such as electric thin film devices, resistive wire devices, platens or other sources of constant temperature. In the embodiment of
The fluid sample has a rate of absorption which is one limiting factor to the speed of the process. The enzymes of the chemistry may also limit. Contrary to the prior art, the present device is limited by only these two constraints. The geometry of other art limits the speed of those processes. Typically, long pathways exist to achieve thermal isolation in such devices.
Once the fluid is placed within the continuous channel 54, various means for moving the sample may be provided such as capillary forces, vacuum, a pressure source or other means. The movement means is illustrated as a first movement means 70 and a second movement means 72. One or both means 70, 72 may be present.
The size, materials and fabrication techniques employed in this embodiment may be selected to most effectively address the needs of the specific application. For example, molding, machining, casting, extruding and various types of metals and plastics may be used for the fluidic device 12. Also, various types of heaters may also be employed. Micro-electrical mechanical systems (MEMS) may also be used to fabricate such a device. Photolithographic processes may result in the creation of multiple layers of dissimilar materials that contain the appropriate pathways, entry and exit ports, and ports through the device. Also, one fluidic device is illustrated. It should be noted that multiple fluidic devices may be employed adjacent to each other in a multiple reaction device. That is, several reactions may take place simultaneously or sequentially within the device. The fluid path may be several individual channels connected in parallel. This may be useful for thermal cycling large volumes of fluid more rapidly. The device may also be disposable in a one-time use application, or may be washed and reused.
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The device may be fabricated using techniques borrowed from thermal ink jet cartridges and integrated chip manufacturing. The device may be formed of silicon and later diced after being bonded together. Alignment features may be incorporated into the device to allow various fixtures to assist in assembling the device.
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The small size, expected low cost and disposable nature of the thermal cycling elements make possible the creation of a random access PCR analyzer. Prior to this embodiment, virtual all PCR reactions were performed as batch operations with the number of different reactions running simultaneously determined by the number of thermal cycling ovens in the system. One type of amplification system has two thermal cyclers and therefore can perform no more than two different protocols simultaneously. As the number of PCR tests increases over time, there will be more demand for random access analyzers. The thermal cycling device may be capable of performing a number of tests. Random access analyzers may be defined as those having the ability to run any combination of available tests on each and every sample presented to the analyzer. Thus, various numbers of heaters or built-in heaters may be provided for each thermal cycling element. Thus, various numbers of samples and various numbers of thermal cycling elements may be simultaneously performed. For example, the amount of heating may be controlled by a central controller so that various temperatures may be achieved in various thermal cycling elements. Random access analyzers have several advantages over batch analyzers. That is, they are faster, more flexible, more versatile, and more productive than batch analyzers. It is envisioned that various PCR kits may be created each containing a multiplicity of thermal cycling elements of a specific type and the necessary reagents to perform PCR amplification. The kits may include the various polymerase enzymes, dNTP's, specially formulated buffers, and primers. Optionally, other agents for sample preparation and detection may also be provided. Thus, by having the capability of programming the temperatures, various PCR test protocol may be run. The incubator 152 may include the means for drawing the fluid through the thermal cycling device. Also, various sample preparations may also be performed such as lysing cellular samples to release DNA or performing reverse transcriptase reaction to create cDNA for RT-PCR.
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External means may also be used to allow recirculation of the PCR amplification product repeatedly through the same or separate devices. Between each of the devices a detection may be performed to determine the amplification.
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As mentioned above, various techniques may be used for fabricating the device. For example, tubes may be preconfigured as set forth in
A method for operating the present invention includes introducing a sample into the device having a plurality of layers. Prior to the introduction of a sample, the temperatures of the individual layers maintain three temperatures required in the PCR protocol. In this embodiment, the temperature of the bottom thermally conductive layer is lower than the upper thermally conductive layer. Thus, once a steady state has been reached by the three conductive layers the sample is introduced into the device. It should be noted that when thermal equilibrium, the entire upper layer is at the same temperature as the temperature source and the entire lower layer is at the temperature of the lower temperature source. Thus, the device is in equilibrium. The middle layer is at an equilibrium temperature between the upper and lower temperatures. The sample is placed through the input port and in the case of the second embodiment, is provided to an initial denaturing stage longer than the other denaturing stages. This may or may not be required depending on the type of PCR performed. The PCR sample is cycled through the first portion of a cycle at the first temperature. The sample is moved to the second layer, which is the lower layer through the third layer in between the first and second layers. The sample also passes through the insulators 24 and 26. Various means may be used to force the fluid through the fluidic device such as a vacuum, a pressure pump, a capillary force or other means. The rate of fluid flow determines the length of time the PCR sample is subjected to the highest temperature in the first portion. After the end of the first portion is performed, the fluid passes to the bottom fluidic layer through the middle layer. After traversing all three channel portions of the first cycle, the fluidic sample enters the second cycle in the first layer. As is illustrated in
It should be noted that various numbers of cycles may be provided in various devices depending on the type of PCR to be performed. Greater or fewer number of cycles may be provided when compared to the 30 PCR cycles of
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This embodiment also may include the various means of heating described above. That is, various platens or other types of heaters may be disposed at various portions of the device. Heaters may be disposed between the insulating layer 214 and the layer 216 or the layer 212, or both. It should also be noted that various numbers of cycles may be provided in the device.
Various embodiments with various numbers of cycles have been illustrated. It should be noted that after or during a cycle variations such as detections or additional denaturing, annealing or extension steps may be performed. For example, an extra denaturing step after the last extension step may be included. Also, elongated denaturing step may be provided at the first cycle portion or first and second cycle portions.
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The upper cap assembly includes a cap housing 270 having a channel 272 therein. The channel 272 receives a platen 274. An end cap 276 is used to secure the platen within the cap piece 270. A rod heater 278 and thermocouple 280 are inserted within an opening 282 in end cap 276. The rod heater is used to heat the platen to a predetermined temperature so that the temperature is imposed upon the fluidic device 12. More specifically, the upper surface of the fluidic device 12 is coupled to the platen 274.
Lower cap assembly 256 includes a lower cap housing 290 that includes a guide feature 292 to be received within the recesses 264 of top 262. A platen 294 is received within the lower cap assembly. A rod heater 296 and a thermocouple 298 are inserted within an opening 300 in an end cap 302 so that the rod heater provides heat to the lower platen 294 and thermocouple 298 is used to heat the platen to a predetermined temperature. Platen 294 may also be coupled to an input tube 310 and an output tube 312. An input channel 314 and an output channel 316 may be provided through the platen. Gaskets 318, 320 may be coupled between the fluidic device 12 and the platen 294 to prevent fluid leakage therebetween. The device is held together with threaded fasteners 340.
A heat sink 350 may be coupled to the lower cap 290. Because the upper platen 274 is at a higher temperature than the lower platen 294, heat is dissipated through the heat sink 350. This helps maintain the denaturing layers and annealing layers of the fluidic device 12 at the predetermined temperatures.
A pair of hose clamps 352, 354 may also be used to secure the input tube 310 and output tube 312 to the thermal cycling device 252.
In one constructed embodiment of the fluidic device, a cross-sectional channel area of 0.022 mm2 was used. The channel length for the denaturing portions was 1 mm and the extension portions 2 mm. Thirty cycles were used in the constructed embodiment. The preliminary denaturation channel length was 9 mm. The thickness of the silicon layers was 0.575 mm. The conductivity was 130 watts/m° C. The polyimide thickness was 0.125 mm and its conductivity was 0.31 watts/m° C.
The reaction solution may include human genomic template DNA of 5 femto molar concentration. A commercial PCR buffer having critical constituents of tris-HCl buffer for pH stability and MgCl2 to provide Mg++ ions critical for polymerase activity. Deoxynucleotide triphosphates (dNTP) were provided of 200 micro molar concentrations each for A, T, C and G. Forward and reverse primers specific to the human genome template which are 20-30 nucleotides in length were chosen to define 100-200 base pair amplicons of 200 micro molar concentrations each. Taq polymerase enzyme was chosen at one unit per reaction. The test fixture described above is coupled to a syringe pump (not shown) from which the reaction solution is pumped through the thermal cycling device 12. The heated platens maintain the denaturation temperatures of 96±1° C. and annealing temperatures of 54±1° C. The platen heaters and temperature controllers having embedded thermocouples provide 16 watts each. A heat sink having a thermal resistance of 3.75° C./w were attached to the exposed surface of the annealing platen. The syringe pumps that were used have a capacity of 10 μL and flow rate of 0.22 μL/s with a 1 mm/s flow rate. The amplification product is collected at the output of the device. Various means may be used to detect the presence and the amount of amplified DNA material present in the product. Common methods employ electrophoresis to spatially separate the PCR products by molecular weight and fluorescence probes that bind to the DNA product to indicate the concentrations.
Forming channel segments in the insulating layer is easier and less expensive than forming the channel segments in the conducting layers. The insulating layers are typically made from a plastic or polymeric material and the channel segments can be easily formed in them by injection molding techniques. This eliminates the expensive etching or other processes described above which can be used to form the channels in the conducting layers.
The device shown in
It is also possible to have the channel “fold back” and provide two or more channel segments in either the annealing or denaturing layer. Similar savings in size and cost could be realized. In addition, there could be multiple folds in any of the layers making the device more compact.
In the multiple layer devices described above, the layers could be of the same or dissimilar materials. FIGS. 24 and 25A/25B depict two devices in which the layers are made of homogeneous materials.
In
While the invention has been described in connection with one or more embodiments, it should be understood that the invention is not limited to those embodiments. On the contrary, the invention is intended to cover all alternatives, modifications, and equivalents, as may be included within the spirit and scope of the appended claims.
Claims
1. A three-layer apparatus for performing a polymerase chain reaction comprising:
- a first thermally conductive layer;
- a second thermally conductive layer;
- a third thermally conductive layer;
- a first insulating layer positioned between said first and second thermally conductive layers;
- a second insulating layer positioned between said second and third thermally conductive layer; and
- a continuous channel having channel segments formed within at least one of said insulating layers, and at least one of said thermally conducting layers;
- said first, second and third thermally conductive layers being positioned one on top of the other forming a multi-layer apparatus.
2. The three-layer apparatus as described in claim 1 wherein one of said channel segments in said first insulating layer is adjacent to said first thermally conductive layer and one of said channel segments in said second insulating layer is adjacent to said third thermally conductive layer.
3. The three-layer apparatus as described in claim 1 wherein said first thermally conductive layer is a denaturing layer, said third thermally conductive layer is an annealing layer, and said second thermally conductive layer is an extension layer.
4. The three-layer apparatus as described in claim 3 wherein at least one of said channel segments extends for a first direction in its respective layer and then reverses itself and extends in the opposite direction in the same layer before proceeding to another layer.
5. The three-layer apparatus as described in claim 4 wherein said at least one of said channel segments extend for said first direction on one side of its respective layer and then reverses itself and extends in said opposite direction on the opposite side of said same layer before proceeding to another layer.
6. The three-layer apparatus as described in claim 5 wherein said respective layer is an extension layer and said at least one of said channel segments is at least partially formed in an insulating layer.
7. The three-layer apparatus as described in claim 1 further comprising at least one temperature source for maintaining said first thermally conductive layer at a first temperature and for maintaining said third thermally conductive layer at a second temperature lower than said first temperature.
8. A two-layer apparatus for performing a polymerase chain reaction comprising:
- a first conducting layer;
- a second conducting layer;
- an insulating layer positioned between said first and second conducting layers;
- a continuous channel having a plurality channel segments, at least one of said channel segments positioned in said insulating layer
- wherein said first conducting layer is positioned on top of said second conducting layer.
9. The two-layer apparatus as described in claim 8 wherein at least one channel segment is adjacent to said first conducting layer and at least one channel segment is positioned adjacent to said second conducting layer.
10. The two-layer apparatus as described in claim 8 further comprising at least one temperature source for maintaining said first and second conducting layers at prespecified temperatures.
11. The two-layer apparatus as described in claim 10 wherein one of said conducting layers has a tab member thereon for connecting to said temperature source.
12. The two-layer apparatus as described in claim 8 wherein at least one channel segment is a denaturing segment, and at least one channel segment is an annealing-extension segment.
13. The two-layer apparatus as described in claim 12 wherein at least two channel segments extend for a first direction in one of said layers and then reverse themselves and extend in the opposite direction in said same layer.
14. The two-layer apparatus as described in claim 12 wherein at least two annealing or denaturing segments are present in the same layer or adjacent the same layer.
15. A method for performing a polymerase chain reaction comprising:
- (a) introducing a sample into a three-layer apparatus, said three-layer apparatus comprising:
- a first thermally conductive layer;
- a second thermally conductive layer;
- a third thermally conductive layer;
- said first, second and third thermally conductive layers being positioned one on top of the other forming a three-layer apparatus;
- a first insulating layer positioned between said first and second thermally conductive layers;
- a second insulating layer positioned between said second and third thermally conductive layer; and
- at least one temperature source for maintaining said first thermally conductive layer at a first temperature and for maintaining said third thermally conductive layer at a second temperature lower than said first temperature;
- a continuous channel having channel segments formed within at least one of said first insulating layers and at least one of said thermally conducting layers;
- (b) performing a first portion of a cycle in a first channel segment at a first temperature;
- (c) moving the sample to another layer;
- (d) thereafter, performing a second portion of the cycle in a second channel segment at a second temperature;
- (e) moving the sample to a second channel segment;
- (f) thereafter, performing a third portion of a cycle in a third channel segment at a third temperature; and
- (g) repeatedly performing the first portion, the second portion and the third portion for a predetermined number of cycles to perform the reaction.
16. A method for performing a polymerase chain reaction comprising:
- (a) introducing a sample into a two-layer apparatus comprising:
- a first conducting layer;
- a second conducting layer;
- said first and second conducting layer being positioned one on top of the other forming a two layer apparatus;
- an insulating layer positioned between said first and second conducting layers; and
- a continuous channel having at least one channel segment within said insulating layer;
- (b) performing a first portion of a cycle in a first channel segment at a first temperature;
- (c) moving the sample to a second channel segment;
- (d) thereafter, performing a second portion of the cycle in said second channel segment at a second temperature;
- (e) moving the sample to a third channel segment;
- (f) thereafter, performing a third portion of a cycle in said third channel segment at a third temperature; and
- repeatedly performing the first portion, the second portion and the third portion for a predetermined number of cycles to perform the reaction.
17. A multi-layer apparatus for performing a polymerase chain reaction comprising:
- a first thermally conductive layer;
- a second thermally conductive layer;
- a third thermally conductive layer;
- a first insulating layer positioned between said first and second thermally conductive layers;
- a second insulating layer positioned between said second and third thermally conductive layers;
- a first heat source for maintaining said first thermally conductive layer at a first temperature; a second heat source for maintaining said third thermally conductive layer at a second temperature lower than said first temperature;
- said first, second and third thermally conductive layers being positioned one on top of the other forming a multi-layer apparatus; and
- a continuous channel formed in said multi-layer apparatus for performing a polymerase chain reaction, said channel having a first channel segment in said first insulating layer adjacent said first thermally conductive layer, and a second channel segment in said first insulating layer adjacent said second thermally conductive layer, a third channel segment in said second insulting layer adjacent said second thermally conductive layer, and a fourth channel segment in said second insulting layer adjacent said third thermally conductive layer.
18. A two-layer apparatus for performing a polymerase chain reaction comprising:
- a first thermally conductive layer;
- a second thermally conductive layer;
- an insulating layer positioned between said first and second thermally conductive layers;
- said first and second thermally conductive layers being substantially the same size and being positioned one on top of the other forming a multi-layer apparatus; and
- a continuous channel formed in said multi-layer apparatus for performing a polymerase chain reaction, said channel having at least one of the channel segments positioned in the insulating layer.
19. A two-layer apparatus as described in claim 18 wherein all of the channel segments are positioned in the insulating layer.
20. A multi-layer PCR device for processing a nucleic acid sample comprising:
- at least two thermally conductive layers;
- at least one insulating layer;
- said thermally conductive layers and said insulating layer and being positioned one on top of the other forming a multi-layer device; and
- a continuous channel in said multi-layer device for circulation and processing of a nucleic acid sample.
21. The device as described in claim 20 further comprising heating sources for heating said thermally conductive layers.
22. The device as described in claim 20 wherein said continuous channel comprises a plurality of channel segments and wherein at least one channel segment is located in said insulating layer.
23. The device as described in claim 22 wherein all of said channel segments are located in said insulating layer.
24. The device as described in claim 20 wherein three thermally conductive layers are provided.
25. The device as described in claim 20 wherein two insulating layers are provided.
26. The device as described in claim 20 wherein three thermally conductive layers and two insulating layers are provided.
27. The device as described in claim 26 wherein said continuous channel has a plurality of channel segments and at least one channel segment is located in one of said insulating layers.
28. The device as described in claim 26 wherein said continuous channel has a plurality of channel segments and at least one channel segment is located in each of said insulating layers.
29. The device as described in claim 26 wherein said continuous channel has a plurality of channel segments and a plurality of said channel segments are located in said insulating layers.
30. The device as described in claim 26 wherein each of said two insulating layers is positioned between two of said thermally conductive layers.
31. The device as described in claim 20 wherein one insulating layer and two thermally conductive layers are provided, and wherein said insulating layer is positioned between said two thermally conductive layers.
32. The device as described in claim 31 wherein said continuous channel comprises a plurality of channel segments and wherein one of said channel segments is located in said insulating layer adjacent to one of said thermally conductive layers.
33. The device as described in claim 26 wherein said first thermally conductive layer is a denaturing layer, said third thermally conductive layer is an annealing layer, and said second thermally conductive layer is an extension layer.
34. The device as described in claim 22 wherein at least one of said channel segments extends for a first direction in its respective layer and then reverses itself and extends in the opposite direction in the same layer before proceeding to another layer.
35. The device as described in claim 30 wherein said continuous channel comprises a plurality of channel segments and wherein one of said channel segments is located in said first insulating layer adjacent to said first thermally conductive layer and one of said channel segments is located in said second insulating layer adjacent to said third thermally conductive layer.
36. The device as described in claim 30 wherein said first thermally conductive layer is a denaturing layer, said third thermally conductive layer is an annealing layer, and said second thermally conductive layer is an extension layer.
37. The device as described in claim 35 wherein at least one of said channel segments extends for a first direction in its respective layer and then reverses itself and extends in the opposite direction in the same layer before proceeding to another layer.
Type: Application
Filed: Oct 24, 2011
Publication Date: Feb 16, 2012
Inventor: Joel Grover (Pittsford, NY)
Application Number: 13/280,145
International Classification: C12P 19/34 (20060101); C12M 1/02 (20060101);