Liquid nitrogen sampling heat preservation storage box and storage method

Abstract

The application discloses a liquid nitrogen sampling heat preservation storage box and a storage method, relates to the technical field of storage devices, and comprises a box body, a box cover arranged on the box body, a liquid nitrogen filling opening arranged on the box body, and a limiting device arranged in the box body. The limiting device comprises a first limiting plate for limiting the bottom surface of a sample placed in a sample bag and a second limiting plate for limiting the top surface of the sample placed in the sample bag. The first limiting plate and the second limiting plate are both hollow structures. The first limiting plate and the second limiting plate are immersed in liquid nitrogen, the overall, rapid and uniform cooling of the sample is realized, and the integrity of nucleic acid is maximally protected. Mechanical damage of the sample caused by the exposure of the sample to the liquid surface due to buoyancy or the collision and friction of the sample with the box cover and the side wall is prevented, and the freezing stability of the sample and the nucleic acid preservation quality under a complex transportation environment in the field are improved.

Description

Technical Field

[0001] This invention relates to the field of storage device technology, specifically to a liquid nitrogen sampling and insulation storage box and storage method. Background Technology

[0002] In plant molecular biology experiments, the quality of nucleic acid (DNA, RNA) extraction from plant leaf samples directly determines the success or failure of the experiment. However, the stability of nucleic acids is highly susceptible to temperature fluctuations; high temperatures or temperature fluctuations can lead to rapid degradation of nucleic acids, rendering them unusable for experimental purposes. When sampling in the field (especially over long distances, in mountainous areas, or along bumpy roads), it is necessary to use liquid nitrogen to rapidly freeze fresh leaf samples and maintain a long-term cryogenic environment to ensure that the samples remain in a low-temperature environment throughout transportation and storage, thus inhibiting nucleic acid degradation.

[0003] Currently, liquid nitrogen storage containers typically introduce liquid nitrogen into the side wall of the storage device before transferring the cooling energy into the storage cavity. This method is not very effective, mainly because the liquid nitrogen first exchanges heat with the container wall, causing the side wall temperature to drop rapidly. However, samples in the central area of ​​the storage cavity often require a longer time to reach the ideal freezing temperature, resulting in insufficient freezing rate. This leads to the formation of ice crystals inside the sample, which damages cell structure and consequently affects the integrity and extraction quality of nucleic acids.

[0004] Therefore, it is necessary to develop and design liquid nitrogen sampling and insulation storage boxes and storage methods that can quickly and uniformly freeze plant leaf samples to meet the requirements of high-quality preservation of nucleic acid samples in plant molecular biology experiments. This is a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0005] To address the aforementioned problems, this invention provides a liquid nitrogen sampling and insulation storage box and storage method. On one hand, liquid nitrogen directly encapsulates the surface of the leaf placed in the bag, achieving overall, rapid, and uniform cooling. On the other hand, the buoyancy generated by the liquid nitrogen, combined with a limiting device, creates a balanced effect, keeping the leaf stably suspended during transportation and preventing mechanical damage caused by shaking, collisions, or air bubble disturbance. This significantly improves the freezing quality and nucleic acid preservation effect of plant leaf samples, making it suitable for sampling in complex field molecular biology experiments.

[0006] To achieve the above objectives, the present invention provides the following solution: A liquid nitrogen sampling and insulation storage box includes a box body, a box cover on the box body, a liquid nitrogen filling port on the box body, and a limiting device disposed inside the box body. The limiting device includes a first limiting plate for limiting the bottom surface of the sample placed in the sample bag and a second limiting plate for limiting the top surface of the sample placed in the sample bag. Both the first limiting plate and the second limiting plate have a hollow structure and are immersed in liquid nitrogen.

[0007] Preferably, the enclosure comprises, from the inside out, a high-density polyurethane insulation layer, a vacuum insulation interlayer, and a high-strength ABS engineering plastic shell.

[0008] Preferably, the inner side wall of the box is provided with at least two slot guide rails, which are inserted into the first limiting plate and the second limiting plate.

[0009] Preferably, the interior of the housing is further provided with a partition plate for dividing the interior of the housing, and the partition plate is inserted into the slot guide rail.

[0010] Preferably, the bottom and all four side walls of the box are covered with a high-elasticity shock-absorbing sponge pad.

[0011] Preferably, the lid is provided with a high-density polyurethane insulation layer and a high-strength ABS engineering plastic shell from the inside out.

[0012] Preferably, a storage slot is provided at the center of the inner side of the lid.

[0013] Preferably, the bottom surface inside the box is provided with a leak-proof groove, and a sealing gasket is laid at the bottom of the leak-proof groove.

[0014] Preferably, a temperature sensor is installed inside the enclosure, and a display screen electrically connected to the temperature sensor is installed on the outer wall of the enclosure.

[0015] This invention also discloses a liquid nitrogen sampling and insulation storage method, which uses the liquid nitrogen sampling and insulation storage box described above and includes the following steps: The sample is placed inside the box and limited by the first limiting plate and the second limiting plate; Add liquid nitrogen and seal the liquid nitrogen filling port, then cover the tank with the lid.

[0016] The present invention achieves the following technical effects compared to the prior art: By installing a perforated first and second limiting plate immersed in liquid nitrogen inside the chamber, the bottom and top surfaces of plant leaf samples are bidirectionally limited. On the one hand, the liquid nitrogen forms a 360° enveloping direct immersion of the sample, and combined with the high permeability of the perforated structure, it achieves overall, rapid, and uniform cooling of the sample, maximizing the protection of nucleic acid integrity. On the other hand, the first and second limiting plates jointly constrain the floating space of the sample in the vertical direction, which not only prevents the sample from being exposed to the liquid surface due to buoyancy or from colliding or rubbing against the chamber lid and side walls, but also avoids the compression of tissues by rigid clamps, significantly improving the freezing stability and nucleic acid preservation quality of samples under complex field transportation environments. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Appendix Figure 1 This is a schematic diagram of the overall structure of the liquid nitrogen sampling and heat preservation storage box disclosed in this invention; Appendix Figure 2 This is a schematic cross-sectional view of the liquid nitrogen sampling and insulation storage box disclosed in this invention. Appendix Figure 3 This is a top view structural diagram of the liquid nitrogen sampling and insulation storage box disclosed in this invention in the open state; Appendix Figure 4 This is a schematic diagram of the longitudinal cross-sectional structure of the liquid nitrogen sampling and heat preservation storage box disclosed in this invention; Appendix Figure 5 This is a schematic diagram of the fitting relationship between the liquid nitrogen filling port and the liquid nitrogen sampling and insulation storage box disclosed in this invention. Appendix Figure 6 This is a schematic diagram of the carrying strap structure of the liquid nitrogen sampling and heat preservation storage box disclosed in this invention; The components include: 1. Lid; 2. Snap-on locking mechanism; 3. Display screen; 4. Box body; 5. Storage compartment; 6. Temperature sensor; 7. Divider; 8. Liquid nitrogen; 9. Sample bag; 10. High-strength ABS engineering plastic shell; 11. Vacuum insulation layer; 12. High-density polyurethane insulation layer; 13. Centrifuge tubes; 14. High-elasticity shockproof sponge padding; 15. Threaded sealing cap; 16. Liquid nitrogen filling port; and 17. Handle. Detailed Implementation

[0019] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] The purpose of this invention is to provide a liquid nitrogen sampling and insulation storage box. On the one hand, liquid nitrogen directly envelops the surface of the leaf placed in the bag, achieving overall, rapid, and uniform cooling. On the other hand, the buoyancy generated by the liquid nitrogen and the limiting device work in balance to keep the leaf in a stable suspended state during transportation, avoiding mechanical damage caused by shaking, collision, or air bubble disturbance. This significantly improves the freezing quality and nucleic acid preservation effect of plant leaf samples, making it suitable for field molecular biology experimental sampling in complex environments.

[0021] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0022] refer to Figures 1-6 The liquid nitrogen sampling and insulation storage box and storage method disclosed in this embodiment of the invention includes at least a box body 4. A box cover 1 is provided on the top of the box body 4. A liquid nitrogen filling port 16 is provided on the side wall of the box body 4. A limiting device is provided inside the box body 4. The limiting device includes a first limiting plate for limiting the bottom surface of the sample placed in the sample bag 9 and a second limiting plate for limiting the top surface of the sample placed in the sample bag 9. Both the first and second limiting plates are hollow structures. The first and second limiting plates are immersed in liquid nitrogen 8. By providing hollow first and second limiting plates immersed in liquid nitrogen 8 inside the box body 4, The bottom and top surfaces of plant leaf samples are bidirectionally confined. On the one hand, liquid nitrogen 8 is used to directly immerse the sample in a 360° enveloping manner without dead angles. Combined with the high permeability of the hollow structure, the sample is cooled in a holistic, rapid and uniform manner, maximizing the protection of nucleic acid integrity. On the other hand, the first and second limiting plates jointly constrain the floating space of the sample in the vertical direction. This not only prevents the sample from being exposed to the liquid surface due to buoyancy or from colliding or rubbing against the box cover 1 and side walls, but also avoids the compression of tissues by rigid clamps. This significantly improves the freezing stability and nucleic acid preservation quality of the samples under complex field transportation conditions.

[0023] The sample is placed in sample bag 9, which provides primary wrapping and isolation protection for the blade. Even when the sample is placed in sample bag 9, the cooling effect of liquid nitrogen on the blade will not have a significant impact. This effectively prevents physical damage or cross-contamination of the blade during sampling, transfer, and placement. The sample bag 9 is made of one of the following materials: nylon, polyester sieve silk, or PTFE (polytetrafluoroethylene / Teflon).

[0024] It should be noted that the liquid nitrogen filling port 16 is provided with an internal thread, which is connected to the external thread of the threaded sealing cap 15. The liquid nitrogen filling port 16 is 3.5cm away from the top of the inner wall of the box 4. Both sides of the outer wall of the box 4 are provided with hanging rings, and the hanging rings are provided with nylon carrying straps 17. The back of the box 4 is provided with two sets of symmetrical shoulder strap fixing points, equipped with adjustable double shoulder straps (nylon material, length can be freely adjusted), which are convenient for carrying in the field or for sampling in mountainous areas, freeing up the hands. The bottom of the box 4 can also be provided with a liquid nitrogen outlet and a sealing device connected to the liquid nitrogen outlet for the liquid nitrogen 8 to be discharged.

[0025] The overall size is lightweight (30cm long × 20cm wide × 25cm high), with a moderate volume that does not take up extra space for sampling equipment. It is easy to put into a sampling backpack or carry alone. The entire insulated storage box has a vertical cuboid structure with rounded corners for impact protection.

[0026] In one embodiment, the enclosure 4 includes a high-density polyurethane insulation layer 12, a vacuum insulation interlayer 11, and a high-strength ABS (acrylonitrile-butadiene-styrene copolymer) engineering plastic shell arranged sequentially from the inside out. The high-density polyurethane insulation layer 12 provides basic thermal insulation, and the vacuum insulation interlayer 11 effectively blocks heat conduction and heat convection. The combination of the two significantly extends the static holding time of liquid nitrogen 8 and reduces the need for frequent replenishment of liquid nitrogen 8 during field operations. The high-strength ABS engineering plastic shell 10 ensures the impact resistance and structural integrity of the enclosure 4 in harsh environments such as bumpy terrain and mountainous areas.

[0027] The high-strength ABS engineering plastic shell 10 has a thickness of 3mm-5mm, and the polyurethane high-density thermal insulation layer has a thickness of 5mm-8mm. The bottom of the high-strength ABS engineering plastic shell 10 has a flat design, which can be placed stably. The liquid nitrogen filling port 16 is connected to the interior of the box 4. The liquid nitrogen filling port 16 is equipped with a threaded sealing cap 15 to achieve sealing and cold resistance.

[0028] In one implementation, the inner wall of the box 4 is provided with at least two slot guide rails, which can be provided both longitudinally and laterally on the inner wall of the box 4. The slot guide rails are inserted into the first limiting plate and the second limiting plate. Scale lines can also be provided on the inner wall of the box 4 to adjust the distance between the first and second limiting plates for different samples. The insertion design of the slot guide rails with the first and second limiting plates enables quick installation, disassembly, and position adjustment of the limiting device within the box 4, facilitating field operation and device cleaning and maintenance. The coexistence of longitudinal and transverse slots allows for flexible changes in the fixing direction and interlayer height of the limiting plates according to the size, shape, and quantity of sample bags 9, making it particularly suitable for mixed packing of plant leaf samples of different sizes or batches. The scale lines provide a visual basis for setting the distance between the first and second limiting plates, allowing users to accurately adjust the space between the upper and lower limiting plates according to the sample thickness. This ensures gentle clamping of the sample bag 9, preventing floating and collision, while avoiding excessive compression that could cause mechanical damage to the leaves.

[0029] As a preferred method, the interior of the box 4 is also equipped with a partition plate 7 for dividing the interior of the box 4. The partition plate 7 can be inserted horizontally or vertically into the slot guide rail as needed, and the size and number of compartments can be freely adjusted to accommodate samples of different specifications (such as 1.5ml / 5ml / 10ml centrifuge tubes 13, cryopreservation tubes, and fresh leaf sample bags of different sizes 9).

[0030] The partition plate 7, the first limiting plate, and the second limiting plate are all made of low-temperature resistant plastic.

[0031] It should be noted that when the partition plate 7 divides the interior of the box 4 into multiple sample storage compartments, slot guide rails can also be opened on the side wall of the partition plate 7 for the first limiting plate and the second limiting plate to engage.

[0032] As a preferred method, the bottom and all four sides of the box 4 are covered with a high-elastic shock-absorbing sponge pad 14 with a thickness of 3mm-4mm, which fits tightly against the inner side wall of the box 4. All sample storage compartments formed by the partitions 7 are wrapped with sponge cushioning to form a fully enclosed shock-absorbing structure.

[0033] It should be noted that the bottom of the box 4 is covered with an integral high-elastic shock-absorbing sponge pad, and the surface of the sponge is treated with anti-slip treatment to prevent the sample containers from sliding. The inner sidewalls of the box 4 are fully wrapped with shock-absorbing sponge lining, which works with the partition plate 7 to form an independent buffer for each compartment, avoiding direct collision between the sample containers and the inner wall. Each compartment is equipped with a dedicated sample fixing slot (honeycomb or single-row design), which is embedded in the inner sponge layer and is specifically used to fix 5ml / 10ml centrifuge tubes 13, further improving the stability of the containers.

[0034] As one implementation method, the cover 1 is provided with a polyurethane high-density insulation layer 12 and a high-strength ABS engineering plastic shell 10 from the inside to the outside, which echoes the polyurethane high-density insulation layer 12 inside the box body 4 and enhances the overall insulation effect.

[0035] It should be noted that an integrated thickened silicone sealing ring (2mm-3mm thick) is set on the inner periphery of the lid 1. The sealing ring fits tightly into the inner groove of the lid 1. When the lid 1 is closed, the sealing ring is press-fitted with the top edge of the box body 4 to achieve complete sealing and cold locking, preventing liquid nitrogen 8 from evaporating and external heat from entering.

[0036] As one implementation method, a storage slot 5 is provided in the center of the inner side of the box cover 1, which is divided into 2-3 small compartments for placing small accessories (labels, markers, disposable gloves, etc.) required for sampling, so that they do not need to be carried separately.

[0037] As one implementation method, a leak-proof groove is provided on the bottom surface inside the housing 4, and a sealing gasket is laid at the bottom of the leak-proof groove to prevent slight leakage of liquid nitrogen 8 and avoid safety hazards.

[0038] As one implementation method, a temperature sensor 6 is installed inside the chamber 4, and a display screen 3 electrically connected to the temperature sensor 6 is installed on the outer wall of the chamber 4. The temperature sensor 6 can continuously collect the real temperature data inside the chamber 4 and display it intuitively on the display screen 3. Operators can keep track of the internal low temperature status at any time without opening the chamber lid 1, avoiding frequent opening of the lid for inspection, which would lead to accelerated evaporation of liquid nitrogen 8 and loss of cold energy. When the liquid nitrogen 8 is insufficient or the insulation performance decreases, causing the temperature inside the chamber 4 to rise abnormally, the display screen 3 can provide early warning information in a timely manner, which makes it convenient for sampling personnel to replenish liquid nitrogen 8 or adjust the sampling plan in advance during field operations, fundamentally preventing the degradation of nucleic acid in leaf samples due to temperature runaway.

[0039] In one implementation, the lid 1 and the body 4 are connected by a hinge, and a snap-locking mechanism 2 is provided at the end of the lid 1 and the body 4 away from the hinge. The hinge connection makes the lid 1 and the body 4 form an integrated flip structure, avoiding the disadvantages of traditional split lids 1 being easily lost in the field and needing to be placed separately. At the same time, it realizes the quick opening and closing and accurate positioning of the lid 1, which is convenient for operators to frequently pick up and put down samples during the sampling process. Two sets of symmetrical snap-locking mechanisms 2 are provided on the outside of the lid 1, which cooperate with the snap-locking seat on the front of the body 4. After closing, the top cover can be firmly locked to prevent the top cover from loosening when bumping in the field and to ensure sealing performance.

[0040] In this invention, all components that come into contact with liquid nitrogen 8 (such as movable partitions and sealing rings) are made of low-temperature resistant materials (capable of withstanding temperatures below -200℃) to prevent components from becoming brittle or broken in low-temperature environments; the high-strength ABS engineering plastic shell 10 and the polyurethane high-density thermal insulation layer meet food-grade / laboratory-grade standards, contain no harmful substances, and prevent contamination of samples; This invention also discloses a liquid nitrogen sampling and insulation storage method, which uses the liquid nitrogen sampling and insulation storage box described above and includes the following steps: S1 Preliminary preparation: According to the sample specifications for this sampling (such as the size of the leaf sample bag 9, the specification of the centrifuge tube 13, and the number of samples), adjust the movable partition inside the chamber 4, insert the card slot guide rail, and divide the chamber into appropriate sizes and numbers of compartments; if equipped with a temperature display screen 3 and sample fixing card slot, confirm that they are working properly. S2 Sample storage: Place freshly collected plant leaf samples into sample bags 9, or into centrifuge tubes 13 or cryopreservation tubes, and place them into the corresponding adjusted inner compartments. If the sample is placed in sample bag 9, it is limited by the first and second limiting plates. If the sample is placed in centrifuge tubes 13 or cryopreservation tubes, ensure that the sample container is stably placed on the shockproof sponge to avoid loosening. S3 Liquid nitrogen filling: Open the threaded sealing cap 15 of the side liquid nitrogen filling port 16, and inject an appropriate amount of liquid nitrogen 8 into the tank 4 through the filling port. After filling, tighten the threaded sealing cap 15 to ensure a seal. S4 Sealing and Locking: Close the top cover and fasten the snap-lock mechanism 2 to ensure that the silicone sealing ring is pressed tightly and sealed to prevent liquid nitrogen 8 from evaporating; put small accessories such as labels, markers, and disposable gloves into the storage compartment 5 inside the top cover; S5 Field Portability: Depending on the sampling environment, select the carrying strap 17 or the adjustable shoulder strap to carry the device to the sampling site or back to the laboratory; the internal temperature can be viewed in real time via the temperature display screen 3 during the journey; S6 Liquid Nitrogen Replenishment: If you carry it for a long time and find that the temperature inside the box rises too quickly or the liquid nitrogen 8 is insufficient, you can replenish liquid nitrogen 8 through the liquid nitrogen filling port 16 without opening the lid. S7 Sample Retrieval: Upon arrival at the laboratory, open the latch, lift the top cover, drain the liquid nitrogen 8, and remove the sample container for subsequent molecular experiments; after use, clean the inner chamber and allow it to air dry for later use.

[0041] It should be noted that, for those skilled in the art, it is obvious that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. A liquid nitrogen sampling and insulation storage box, characterized in that, The device includes a housing (4), a lid (1) covering the housing (4), a liquid nitrogen filling port (16) opened on the housing (4), and a limiting device disposed inside the housing (4). The limiting device includes a first limiting plate for limiting the bottom surface of the sample placed in the sample bag (9) and a second limiting plate for limiting the top surface of the sample placed in the sample bag (9). Both the first limiting plate and the second limiting plate are hollow structures and are immersed in liquid nitrogen (8).

2. The liquid nitrogen sampling and insulation storage box according to claim 1, characterized in that, The enclosure (4) includes a polyurethane high-density insulation layer (12), a vacuum insulation interlayer (11), and a high-strength ABS engineering plastic shell (10) arranged sequentially from the inside to the outside.

3. The liquid nitrogen sampling and insulation storage box according to claim 1, characterized in that, The inner side wall of the box (4) is provided with at least two slot guide rails, which are inserted into the first limiting plate and the second limiting plate.

4. The liquid nitrogen sampling and insulation storage box according to claim 3, characterized in that, The box (4) is also provided with a partition plate (7) for dividing the interior of the box (4), and the partition plate (7) is inserted into the slot guide rail.

5. The liquid nitrogen sampling and insulation storage box according to claim 1, characterized in that, The bottom and all four sides of the box (4) are covered with a high-elasticity shock-absorbing sponge pad (14).

6. The liquid nitrogen sampling and insulation storage box according to claim 1, characterized in that, The lid (1) is provided with a polyurethane high-density insulation layer (12) and a high-strength ABS engineering plastic shell (10) from the inside to the outside.

7. The liquid nitrogen sampling and insulation storage box according to claim 1, characterized in that, A storage compartment (5) is provided at the center of the inner side of the box cover (1).

8. The liquid nitrogen sampling and insulation storage box according to claim 1, characterized in that, The bottom surface inside the box (4) is provided with a leak-proof groove, and a sealing gasket is laid at the bottom of the leak-proof groove.

9. The liquid nitrogen sampling and insulation storage box according to claim 1, characterized in that, A temperature sensor (6) is installed inside the housing (4), and a display screen (3) electrically connected to the temperature sensor (6) is installed on the outer wall of the housing (4).

10. A method for liquid nitrogen sampling and thermal insulation storage, using the liquid nitrogen sampling and thermal insulation storage box according to any one of claims 1-9, characterized in that, Includes the following steps: The sample is placed inside the box (4) and limited by the first limiting plate and the second limiting plate; Add liquid nitrogen (8) and seal the liquid nitrogen filling port (16), and cover the box with the lid (1).

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