Isothermal amplification heating device and method based on phase change material
By leveraging the exothermic crystallization of supersaturated hydrated salt solutions and the phase change properties of phase change materials, isothermal gene amplification without the need for a power source was achieved, solving the problem of equipment dependence on power and providing a portable, low-cost nucleic acid detection solution.
Patent Information
- Application Number
- CN202511120608.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-08-12
- Publication Date
- 2025-11-14
AI Technical Summary
Existing isothermal gene amplification detection technology equipment requires power and batteries, making it difficult to use in environments without power, and the equipment is complex and not easy to carry.
The exothermic crystallization reaction of a supersaturated hydrated salt solution provides the initial heat, which is combined with a phase change material layer to maintain a constant temperature. Temperature control is achieved through the solid-liquid phase change characteristics of the phase change material, eliminating the need for thermal sensors and power supply dependence.
It achieves isothermal gene amplification without external power supply. The device is portable, low-cost, suitable for power-free environments, has precise temperature control, strong adaptability, and meets the needs of instant detection.
Smart Images
Figure CN120944688A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of biological detection technology, specifically to an isothermal amplification heating device and method based on phase change materials. Background Technology
[0002] Gene amplification technology has wide applications in many fields, including biological research, molecular medicine detection, crime scene analysis, and agricultural and livestock testing. Compared to traditional detection methods, gene amplification detection typically offers higher sensitivity and specificity. Polymerase chain reaction (PCR) is the most representative gene amplification technique, generally consisting of three steps: 1) Denaturing double-stranded DNA into single-stranded DNA at 95°C; 2) At a low temperature (50-65°C), primers bind to single-stranded DNA according to the complementary base pairing principle; 3) Raising the temperature to the polymerase reaction temperature (usually 72°C), the polymerase synthesizes the complementary strand to the single-stranded DNA along the 5' to 3' direction. Theoretically, after one cycle, the number of target gene sequences will increase twofold, and another thermal cycle can begin from the first step, completing exponential amplification of the target gene. The specificity of amplification usually depends on primer design and the primer-single-stranded DNA binding temperature. Some improved PCR methods combine the second and third steps, thus omitting the amplification temperature control step. However, the PCR method requires cycling through at least two temperature ranges and has strict temperature control requirements, which makes the design of PCR instruments more complex, and the detection generally needs to be performed in a laboratory.
[0003] In recent years, isothermal gene amplification technology has rapidly developed as a novel gene amplification method. Its key feature is that the gene amplification reaction is completed at a constant temperature, eliminating the need for repeated thermal cycling steps in PCR. Currently, various isothermal amplification methods have emerged, including NASBA (Nucleic Acid-Dependent Amplification), RPA (Recombinase Polymerase Amplification), RAA (Recombinase-Assisted Amplification), MIRA (Multi-Enzyme Isothermal Nucleic Acid Amplification), ERA (Enzyme-Catalyzed Recombinase Isothermal Amplification), SDA (Strand Displacement Amplification), HDA (Helicase-Dependent Amplification), and RCA (Rolling Circle Amplification). These methods have different reaction principles, resulting in slight differences in the reaction systems used and consequently, varying isothermal amplification temperatures. For example, NASBA is typically performed at around 41°C, while RPA operates at around 37-42°C. Although isothermal gene amplification eliminates the need for thermal cycling between multiple temperatures, temperature control is still required. A common method is to use electric heating with a thermal sensor. Although this temperature control system is relatively simpler than PCR instruments, it usually still requires a power source or a large-capacity battery, which greatly limits the practical application of isothermal gene detection outside the laboratory, such as in the field or remote areas.
[0004] Therefore, developing a isothermal gene amplification heating method based on phase change materials, which heats the phase change material through an exothermic reaction and utilizes the physical melting process of the phase change material to maintain a certain temperature for isothermal gene amplification reaction, without the need for thermal sensors, power supplies, and large-capacity batteries, has become an important research direction for those skilled in the art. Summary of the Invention
[0005] In view of this, to address the problems of existing isothermal amplification detection technologies where instruments or equipment require power, are expensive, and are not portable, the present invention aims to propose an isothermal amplification heating device and method based on phase change materials. By combining isothermal amplification and nucleic acid detection test strips, it achieves the goal of visual nucleic acid detection without power supply or instruments, realizing the elimination of external power supply and thermal sensor requirements, low cost, and portability of the device.
[0006] To achieve the above objectives, the present invention provides the following technical solution:
[0007] To achieve the above objectives, in a first aspect, the present invention provides an isothermal amplification heating device based on phase change materials, comprising:
[0008] A supersaturated solution container for containing a supersaturated hydrated salt solution that releases heat when crystallization is triggered;
[0009] A phase change material layer surrounds the supersaturated solution container. The phase change temperature of the phase change material matches the target isothermal amplification temperature. It is used to absorb the heat released by the crystallization of the hydrated salt solution and maintain isothermal temperature through solid-liquid phase change.
[0010] The reaction vessel, placed within the phase change material layer, is used to load nucleic acid amplification reagents and achieves constant-temperature heating through the thermal conductivity of the phase change material.
[0011] A triggering device is used to initiate the exothermic crystallization of the supersaturated hydrated salt solution.
[0012] As a further aspect of the present invention, the supersaturated hydrated salt solution is selected from at least one of sodium acetate, sodium carbonate decahydrate, sodium thiosulfate pentahydrate, sodium sulfate decahydrate, calcium chloride hexahydrate, and calcium nitrate tetrahydrate.
[0013] As a further aspect of the present invention, the phase change material is at least one of paraffin, straight-chain alkanes, olefins, and hydrated salts (such as sodium acetate trihydrate), and its phase change temperature is 30-60°C.
[0014] As a further embodiment of the present invention, the triggering device is a seed input device, a physical disturbance device (friction on the inner wall or vibration of the container), a metal sheet vibration or a sharp and rough metal.
[0015] As a further embodiment of the present invention, the reaction vessel is a sealed structure with a lid, disposed within the phase change material layer.
[0016] As a further aspect of the present invention, the ratio of the volume of the phase change material layer to the volume of the supersaturated solution is 1:5 to 1:10.
[0017] As a further embodiment of the present invention, the supersaturated solution container is container I, which is used to contain a supersaturated sodium acetate solution and release heat through crystallization; the phase change material layer is container II, which is used to wrap the supersaturated solution container, absorb the heat released by its crystallization, and maintain a constant temperature by utilizing phase change characteristics (such as the solid-liquid phase change of paraffin); the reaction container is container III, which is placed inside the phase change material layer and is used to load nucleic acid amplification reagents and indirectly heat them through the phase change material.
[0018] As a further embodiment of the present invention, the containers I, II and III are three cylindrical containers. Container I has a diameter of 20 mm and a height of 55 mm; container II has a diameter of 12.5 mm and a height of 30 mm; and container III has a diameter of 9 mm and a height of 25 mm. A 30 mm long iron wire is horizontally pierced through the three cylindrical containers at a height of 20 mm.
[0019] As a further embodiment of the present invention, the supersaturated hydrated salt solution in container I is 11 mL of added supersaturated sodium acetate solution, and the phase change material in container II is 1.5 mL of added paraffin wax with a phase change temperature of 42°C; container III is placed in the center of container II, and when the paraffin wax cools to room temperature, container II containing container III is placed in the center of container I.
[0020] Secondly, the present invention also provides an isothermal amplification heating method based on phase change materials, comprising the following steps:
[0021] A supersaturated hydrated salt solution is placed in a container and coated with a phase change material layer;
[0022] The crystallization of the hydrated salt solution is triggered by exothermic reaction, causing the phase change material to absorb heat and undergo a phase change.
[0023] By utilizing the isothermal properties of phase change materials, the nucleic acid amplification reagent in the reaction vessel is heated to the target temperature, with temperature fluctuation ≤2℃, for more than 20 minutes.
[0024] As a further embodiment of the present invention, the target temperature is 37-42℃, used for RPA (recombinase polymerase amplification), RAA (recombinase-assisted amplification), MIRA (multi-enzyme isothermal rapid nucleic acid amplification), and ERA (enzyme-catalyzed recombination isothermal amplification).
[0025] As a further aspect of the present invention, the isothermal amplification heating method further includes combining the amplification product with a nucleic acid test strip for real-time nucleic acid visualization detection, forming a portable real-time nucleic acid detection device that requires no power supply throughout the entire process.
[0026] Compared with existing technologies, the isothermal amplification heating device and method based on phase change materials proposed in this invention have the following beneficial effects:
[0027] 1. Completely eliminates dependence on external power supply, achieving passive operation.
[0028] This invention utilizes the exothermic crystallization reaction of supersaturated hydrated salts (such as sodium acetate) to provide initial heat, while phase change materials (such as paraffin) maintain the temperature by absorbing and storing latent heat. No external power source or large-capacity battery is required, making it suitable for scenarios without stable power supply, such as in the field, disaster areas, and primary healthcare, thus solving the dependence of traditional equipment on power infrastructure.
[0029] 2. No complex temperature control system is required, reducing equipment complexity.
[0030] In this invention, the solid-liquid phase change properties of the phase change material (PCM) can achieve automatic temperature buffering near its melting point (e.g., 42°C paraffin), with temperature fluctuations ≤2°C. By utilizing the material's physical properties to naturally control the temperature, sensors, circuits, and software algorithms are eliminated, simplifying the equipment structure. There are no precision temperature control components, thus reducing the cost of use.
[0031] 3. The device has been miniaturized.
[0032] This invention can be handheld or integrated into a reagent kit, making it highly portable. Compared to traditional isothermal amplification equipment that requires a power supply and temperature control module, this invention only has a nested tubular structure, greatly reducing its size. By changing the type of phase change material or adjusting the concentration of the supersaturated solution, it can cover the temperature requirements of various amplification technologies. The temperature is flexibly adjustable, reducing development costs.
[0033] 4. It achieves rapid start-up and long-term constant temperature maintenance.
[0034] This invention rapidly releases heat through crystallization of a supersaturated solution, improving the start-up speed. The temperature of the reaction solution rises from room temperature to the target temperature within 5 minutes, and the latent heat release of the phase change material can last for more than 30 minutes, satisfying most isothermal amplification reactions. Compared with electric heating which requires preheating time, this method can be used immediately after triggering, saving the total detection time. Moreover, the phase change material has a buffering effect on external temperature fluctuations and is highly adaptable to the environment.
[0035] In summary, this invention achieves passive, miniaturized, and low-cost isothermal amplification technology through the energy conversion and temperature control mechanism of supersaturated solution-phase change material, while also possessing advantages such as temperature stability, rapid response, and ease of operation. The performance of this invention fully meets the requirements of point-of-care testing (POCT), solves the dependence of traditional technologies on power supply, instruments, and professional operation, and provides a breakthrough solution for the popularization of molecular diagnostics in resource-limited scenarios.
[0036] These or other aspects of this application will become more apparent from the following description of embodiments. It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only, and are not intended to limit the application. Attached Figure Description
[0037] To more clearly illustrate the technical solutions in the embodiments of the present invention or related technologies, the accompanying drawings used in the description of the exemplary embodiments or related technologies will be briefly introduced below. The drawings are used to provide a further understanding of the present invention and constitute a part of the specification. They are used together with the embodiments of the present invention to explain the present invention and do not constitute a limitation thereof. In the drawings:
[0038] Figure 1 This is a schematic diagram of the isothermal amplification heating device based on phase change materials according to an embodiment of the present invention.
[0039] Figure 2 This is a flowchart of the isothermal amplification heating method based on phase change materials according to an embodiment of the present invention. Detailed Implementation
[0040] The present application will now be further described in conjunction with the accompanying drawings and specific embodiments. It should be noted that, without conflict, the various embodiments or technical features described below can be arbitrarily combined to form new embodiments.
[0041] To make the objectives, technical solutions, and advantages of the present invention clearer, the embodiments of the present invention will be further described in detail below with reference to specific examples and the accompanying drawings. It should be understood that the specific embodiments described herein are merely illustrative and are not intended to limit the scope of this application.
[0042] It should be noted that all uses of "first" and "second" in the embodiments of the present invention are for the purpose of distinguishing two different entities or different parameters with the same name. Therefore, "first" and "second" are merely for convenience of expression and should not be construed as limiting the embodiments of the present invention. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion, such as other steps or units inherent in a process, method, system, product, or device that includes a series of steps or units.
[0043] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.
[0044] The flowchart shown in the attached diagram is for illustrative purposes only and does not necessarily include all content and operations / steps, nor does it necessarily have to be performed in the order described. For example, some operations / steps can be broken down, combined, or partially merged, so the actual execution order may change depending on the actual situation.
[0045] The following detailed description of some embodiments of this application is provided in conjunction with the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.
[0046] To address the issues that existing isothermal amplification detection technologies require power supplies, are expensive, and are not portable, this invention proposes an isothermal amplification heating device and method based on phase change materials. By combining isothermal amplification and nucleic acid detection test strips, it achieves the goal of visual nucleic acid detection without power supply or instruments, realizing the elimination of external power supply and thermal sensor requirements, low cost, and portability of the device.
[0047] See Figure 1 As shown, an embodiment of the present invention provides an isothermal amplification heating device based on phase change material, including a supersaturated solution container, a phase change material layer, a reaction container, and a triggering device. The supersaturated solution container holds a supersaturated hydrated salt solution, which releases heat upon triggered crystallization. The phase change material layer encloses the supersaturated solution container, and the phase change temperature of the phase change material matches the target isothermal amplification temperature, absorbing the heat released by the crystallization of the hydrated salt solution and maintaining isothermal temperature through a solid-liquid phase change. The reaction container is placed within the phase change material layer and is used to load nucleic acid amplification reagents, achieving isothermal heating through the thermal conductivity of the phase change material. The triggering device is used to initiate the exothermic crystallization of the supersaturated hydrated salt solution.
[0048] In this embodiment, the supersaturated hydrated salt solution is selected from at least one of sodium acetate, sodium carbonate decahydrate, sodium thiosulfate pentahydrate, sodium sulfate decahydrate, calcium chloride hexahydrate, and calcium nitrate tetrahydrate. Preferably, the supersaturated hydrated salt solution is selected from a supersaturated sodium acetate solution.
[0049] In this embodiment, the phase change material is at least one selected from paraffin, straight-chain alkanes, olefins, and hydrated salts (sodium acetate trihydrate), and its phase change temperature is 30-60°C. Preferably, in this embodiment, the phase change material is paraffin.
[0050] The triggering device can be a seed crystal feeding device, a physical disturbance device (friction on the inner wall or vibration of the container), a vibrating metal sheet, or a sharp, rough metal. In this embodiment, the triggering device is a seed crystal feeding device. The reaction container is a sealed structure with a lid and is disposed within the phase change material layer. The volume ratio of the phase change material layer to the supersaturated solution is 1:5 to 1:10.
[0051] See Figure 1 As shown, an embodiment of the present invention provides a isothermal amplification heating device based on phase change materials. The supersaturated solution container is container I10, which is used to contain a supersaturated sodium acetate solution and release heat through crystallization. The phase change material layer is container II20, which is used to wrap the supersaturated solution container, absorb the heat released by its crystallization, and maintain constant temperature by utilizing phase change characteristics (such as solid-liquid phase change of paraffin). The reaction container is container III30, which is placed inside the phase change material layer and is used to load nucleic acid amplification reagents and indirectly heat through the phase change material.
[0052] The containers I10, II20, and III30 are three cylindrical containers. Container I10 has a diameter of 20 mm and a height of 55 mm; container II20 has a diameter of 12.5 mm and a height of 30 mm; and container III30 has a diameter of 9 mm and a height of 25 mm. A 30 mm long iron wire 40 is horizontally pierced through the three cylindrical containers at a height of 20 mm.
[0053] The supersaturated hydrated salt solution in container I10 is 11 mL of added supersaturated sodium acetate solution, and the phase change material in container II20 is 1.5 mL of added paraffin wax with a phase change temperature of 42°C; container III30 is placed in the center of container II20, and when the paraffin wax cools to room temperature, container II20 containing container III30 is placed in the center of container I10.
[0054] 50 μL of liquid was added to container III30, and then a small amount of crystals were added to the supersaturated sodium acetate solution using a seed crystal feeding device. At this point, the supersaturated sodium acetate solution began to crystallize and release heat. Paraffin (melting point 42°C) absorbed the heat released by the crystallization of the supersaturated sodium acetate solution, thereby heating the 50 μL of liquid in container III30. The following temperatures were finally measured:
[0055] First temperature measurement:
[0056] time 1 minute 2 minutes 3 minutes 4 minutes 5 minutes Temperature (°C) 33.1 38.0 39.6 40.8 42.2 time 6 minutes 7 minutes 8 minutes 9 minutes 10 minutes Temperature (°C) 43.0 43.2 42.9 42.7 42.3 time 11 minutes 12 minutes 13 minutes 14 minutes 15 minutes Temperature (°C) 41.9 41.5 41.1 40.8 40.6
[0057] Second temperature measurement:
[0058]
[0059]
[0060] Third temperature measurement:
[0061] time 1 minute 2 minutes 3 minutes 4 minutes 5 minutes Temperature (°C) 33.9 38.2 40.2 42.1 43.0 time 6 minutes 7 minutes 8 minutes 9 minutes 10 minutes Temperature (°C) 43.3 43.5 43.5 43.4 43.2 time 11 minutes 12 minutes 13 minutes 14 minutes 15 minutes Temperature (°C) 43.0 42.5 42.2 41.8 41.5
[0062] This invention relates to a isothermal amplification heating device based on phase change materials. It requires no external power source, heating through a chemical reaction, thus reducing operating costs and equipment complexity. Furthermore, the isothermal properties of phase change materials eliminate the need for thermal sensors for temperature measurement and control, simplifying the device structure. Because it eliminates the need for a complex temperature control system and external power source, the overall cost is low, with heating costs as low as 2 yuan or even less. This makes it suitable as a disposable consumable, facilitating its application in primary healthcare units and remote areas. The device is also portable, requiring no power source for heating or sensor-controlled temperature, and the entire device is miniaturized, eliminating the need for various electronic components.
[0063] See Figure 2 As shown, embodiments of the present invention also provide an isothermal amplification heating method based on phase change materials. The method is executed using the aforementioned isothermal amplification heating device and includes the following steps:
[0064] Step S101: Place the supersaturated hydrated salt solution in a container and wrap it with a phase change material layer;
[0065] Step S102: Trigger the exothermic crystallization of the hydrated salt solution, causing the phase change material to absorb heat and undergo a phase change;
[0066] Step S103: Utilize the isothermal properties of phase change materials to heat the nucleic acid amplification reagent in the reaction vessel to the target temperature, with temperature fluctuation ≤2℃, for more than 20 minutes.
[0067] The target temperature is 37-42℃, used for RPA (recombinase polymerase amplification), RAA (recombinase-assisted amplification), MIRA (multi-enzyme isothermal rapid nucleic acid amplification), and ERA (enzyme-catalyzed recombination isothermal amplification).
[0068] In this embodiment, the isothermal amplification heating method further includes combining the amplification product with a nucleic acid test strip for real-time nucleic acid visualization detection, forming a portable real-time nucleic acid detection device that requires no power throughout the entire process. When performing this isothermal amplification heating method based on phase change materials, paraffin is heated by the exothermic crystallization of a supersaturated solution, and a small amount of liquid is heated by storing energy and controlling the temperature using the phase change material.
[0069] In some embodiments, supersaturated sodium acetate itself possesses the characteristics of a phase change material, allowing the concentration of supersaturated sodium acetate to be directly adjusted to achieve the desired temperature. The type of supersaturated solution can also be changed, for example, hydrated salts such as sodium carbonate decahydrate (Na₂CO₃·10H₂O), sodium thiosulfate pentahydrate (hypo, Na₂S₂O₃·5H₂O), sodium sulfate decahydrate (sodium sulfate, Na₂SO₄·10H₂O), calcium chloride hexahydrate (CaCl₂·6H₂O), calcium nitrate tetrahydrate (Ca(NO₃)₂·4H₂O), sodium sulfate decahydrate (Na₂SO₄·10H₂O), disodium hydrogen phosphate dodecahydrate (Na₂HPO₄·12H₂O), their corresponding anhydrous compounds, and mixtures of various supersaturated solutions.
[0070] In some embodiments, the type of phase change material can also be changed, such as aliphatic hydrocarbon phase change materials like straight-chain alkanes, alkenes, and branched alkanes, as well as hydrated salts and corresponding anhydrous compounds such as sodium acetate trihydrate (CH3COONa·3H2O), sodium carbonate decahydrate (Na2CO3·10H2O), sodium thiosulfate pentahydrate (hypo, Na2S2O3·5H2O), sodium sulfate decahydrate (sodium sulfate, Na2SO4·10H2O), calcium chloride hexahydrate (CaCl2·6H2O), calcium nitrate tetrahydrate (Ca(NO3)2·4H2O), sodium sulfate decahydrate (Na2SO4·10H2O), and disodium hydrogen phosphate dodecahydrate (Na2HPO4·12H2O). Materials meeting the following definition are all phase change materials: a phase change material (PCM) is a substance that changes its state of matter while maintaining a constant temperature and can provide latent heat. The process of changing physical properties is called a phase transition process, during which the phase change material will absorb or release a large amount of latent heat.
[0071] In some embodiments, the shape of the heated container can also be changed, for example... Figure 1 Containers II20 and III30 can be made with lids, making the entire heating device airtight and portable. Additionally, the crystallization method of a supersaturated solution can be altered.
[0072] 1) Seeding operation: Adding crystals (seeds) to a supersaturated solution as a crystallization starting point can instantly trigger a chain of crystallization with significant exothermic effects.
[0073] 2) Physical disturbances. For example, rubbing the inner wall of the container: scraping the inner wall of the container with a glass rod or metal sheet to create microcrystal nuclei. Vibration or knocking: slightly vibrating the solution to break the metastable state. Or, inserting a sharp object with crystals or a rough surface into the outside of the container containing the supersaturated solution.
[0074] 3) Metal sheet induction. Insert a metal sheet (such as stainless steel) or an ice pack into the solution surface to trigger crystallization through temperature difference or surface roughness.
[0075] This invention relates to an isothermal amplification heating device and method based on phase change materials. It utilizes the exothermic crystallization reaction of supersaturated hydrated salts (such as sodium acetate) to provide initial heat, while the phase change material (such as paraffin) maintains temperature by absorbing and storing latent heat. No external power source or high-capacity battery is required, making it suitable for scenarios without stable power supply, such as in the field, disaster areas, and primary healthcare settings, thus solving the dependence of traditional equipment on power infrastructure. The solid-liquid phase change characteristics of the phase change material (PCM) in this invention enable automatic temperature buffering near its melting point (e.g., 42°C paraffin), with temperature fluctuations ≤2°C. Utilizing the material's physical properties for natural temperature control eliminates the need for sensors, circuits, and software algorithms, simplifying the device structure and reducing operating costs. This invention can be handheld or integrated into a reagent kit, making it highly portable. Compared to traditional isothermal amplification devices that require power supplies and temperature control modules, this invention uses only a nested tubular structure, significantly reducing its size. By changing the type of phase change material or adjusting the concentration of the supersaturated solution, it can cover the temperature requirements of various amplification technologies, offering flexible temperature adjustment and reducing development costs. This invention rapidly releases heat through crystallization of a supersaturated solution, improving the start-up speed. The temperature of the reaction solution rises from room temperature to the target temperature within 5 minutes, and the latent heat release of the phase change material can last for more than 30 minutes, satisfying most isothermal amplification reactions. Compared with electric heating which requires preheating time, this method can be used immediately after triggering, saving the total detection time. Moreover, the phase change material has a buffering effect on external temperature fluctuations and is highly adaptable to the environment.
[0076] In summary, this invention achieves passive, miniaturized, and low-cost isothermal amplification technology through the energy conversion and temperature control mechanism of supersaturated solution-phase change material, while also possessing advantages such as temperature stability, rapid response, and ease of operation. The performance of this invention fully meets the requirements of point-of-care testing (POCT), solves the dependence of traditional technologies on power supply, instruments, and professional operation, and provides a breakthrough solution for the popularization of molecular diagnostics in resource-limited scenarios.
[0077] The above are exemplary embodiments disclosed in this invention. However, it should be noted that various changes and modifications can be made without departing from the scope of the embodiments of this invention as defined by the claims. The functions, steps, and / or actions of the methods according to the disclosed embodiments described herein do not need to be performed in any particular order. Furthermore, although the elements disclosed in the embodiments of this invention may be described or claimed individually, they may be understood as multiple unless explicitly limited to a singular number.
[0078] It should be understood that, as used herein, the singular form "a" is intended to include the plural form as well, unless the context clearly supports an exception. It should also be understood that, as used herein, "and / or" refers to any and all possible combinations of one or more of the associatedly listed items. The embodiment numbers disclosed above are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.
[0079] Those skilled in the art should understand that the discussion of any of the above embodiments is merely exemplary and is not intended to imply that the scope of the invention (including the claims) is limited to these examples. Within the framework of the invention, technical features of the above embodiments or different embodiments can be combined, and many other variations of different aspects of the invention exist, which are not provided in the details for the sake of brevity. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the invention should be included within the protection scope of the invention.
Claims
1. A isothermal amplification heating device based on phase change materials, characterized in that, include: A supersaturated solution container for containing a supersaturated hydrated salt solution that releases heat when crystallization is triggered; A phase change material layer surrounds the supersaturated solution container. The phase change temperature of the phase change material matches the target isothermal amplification temperature. It is used to absorb the heat released by the crystallization of the hydrated salt solution and maintain isothermal temperature through solid-liquid phase change. The reaction vessel, placed within the phase change material layer, is used to load nucleic acid amplification reagents and achieves constant-temperature heating through the thermal conductivity of the phase change material. A triggering device is used to initiate the exothermic crystallization of the supersaturated hydrated salt solution.
2. The isothermal amplification heating device based on phase change materials as described in claim 1, characterized in that, The supersaturated hydrated salt solution is selected from at least one of sodium acetate, sodium carbonate decahydrate, sodium thiosulfate pentahydrate, sodium sulfate decahydrate, calcium chloride hexahydrate, and calcium nitrate tetrahydrate.
3. The isothermal amplification heating device based on phase change materials as described in claim 2, characterized in that, The phase change material is at least one of paraffin, straight-chain alkanes, olefins, and hydrated salts, and the phase change temperature is 30-60℃.
4. The isothermal amplification heating device based on phase change materials as described in claim 1, characterized in that, The triggering device is a seed crystal insertion device, a physical disturbance device, a metal sheet vibration device, or a sharp or rough metal.
5. The isothermal amplification heating device based on phase change materials as described in claim 3, characterized in that, The reaction vessel is a sealed structure with a lid and is located inside the phase change material layer.
6. The isothermal amplification heating device based on phase change materials as described in claim 5, characterized in that, The volume ratio of the phase change material layer to the supersaturated solution is 1:5 to 1:
10.
7. The isothermal amplification heating device based on phase change materials as described in claim 6, characterized in that, The supersaturated solution container is container I, which is used to contain a supersaturated sodium acetate solution and releases heat through crystallization; the phase change material layer is container II, which is used to wrap the supersaturated solution container, absorb the heat released by its crystallization, and maintain a constant temperature by utilizing the phase change properties; the reaction container is container III, which is placed inside the phase change material layer and is used to load nucleic acid amplification reagents and indirectly heat them through the phase change material.
8. The isothermal amplification heating device based on phase change materials as described in claim 7, characterized in that, Container I, Container II, and Container III are three cylindrical containers, and a wire is horizontally pierced through each of the three cylindrical containers.
9. The isothermal amplification heating device based on phase change materials as described in claim 8, characterized in that, The supersaturated hydrated salt solution in container I is a supersaturated sodium acetate solution, and the phase change material in container II is paraffin with a phase change temperature of 42°C. Container III is placed in the center of container II. When the paraffin cools to room temperature, container II containing container III is placed in the center of container I.
10. A method for isothermal amplification heating based on phase change materials, characterized in that, The method is performed using the isothermal amplification heating apparatus based on phase change materials according to any one of claims 1-9, and the method includes the following steps: A supersaturated hydrated salt solution is placed in a container and coated with a phase change material layer; The crystallization of the hydrated salt solution is triggered by exothermic reaction, causing the phase change material to absorb heat and undergo a phase change. Utilizing the isothermal properties of phase change materials, the nucleic acid amplification reagent in the reaction vessel is heated to the target temperature, with temperature fluctuation ≤2℃, for more than 20 minutes.