Preparation process of biological ultrafiltration centrifuge tube

Abstract

The invention relates to the field of manufacturing of biological experiment consumables, and discloses a preparation process of a biological ultrafiltration centrifuge tube, which comprises the following steps: S1, mounting ultrafiltration membranes at the bottom of the inner wall of the ultrafiltration centrifuge tube, and ensuring that the ultrafiltration membranes are uniformly distributed; s2, the installed ultrafiltration centrifugal tube is placed at the transmitting end of the improved ultrasonic welding equipment; s3, ultrasonic waves act on the welding portion of the ultrafiltration centrifugal tube in a concentrated mode, and ultrasonic welding is completed through directionally-transmitted sound waves; and S4, after welding is completed, cooling the ultrafiltration centrifugal tube, and detecting the aperture completeness of an ultrafiltration membrane in the ultrafiltration centrifugal tube and the sealing of a welding part. A multi-layer barrier film structure is designed at the transmitting end of ultrasonic welding equipment, the energy influence of ultrasonic waves on a non-welding area is remarkably reduced by utilizing the reflection and attenuation mechanism of sound waves, and the damage to the microporous structure of the ultrafiltration membrane in the traditional welding process is avoided.

Description

Technical Field

[0001] The present invention relates to the technical field of manufacturing biological experiment consumables, and particularly to a preparation process of a biological ultrafiltration centrifuge tube. Background Art

[0002] As an important experimental consumable, the ultrafiltration centrifuge tube is widely used in the fields of life science research, medical testing, drug development, etc. It plays an important role especially in the concentration, purification and buffer replacement of biological samples such as proteins, antibodies, nucleic acids, viruses, exosomes, etc. Through the built-in ultrafiltration membrane, the ultrafiltration centrifuge tube can efficiently separate and enrich the target molecules in biological samples, while excluding small molecule impurities, meeting the precision requirements of subsequent analysis and experiments. In addition, the ultrafiltration centrifuge tube can also play an important role in drug screening, drug binding experiments, protein enrichment and sample pretreatment for analysis, and is an indispensable tool in biological and medical experiments.

[0003] The core component of the ultrafiltration centrifuge tube is the built-in ultrafiltration membrane, and its microporous structure determines the filtration efficiency and separation effect. However, due to the extremely small pore size of the ultrafiltration membrane (molecular level, usually 0.01 - 0.1 micrometers) and its fragile structure, it is extremely vulnerable to the influence of mechanical, thermal or acoustic energy during processing and use, resulting in pore size deformation, rupture or damage. In order to ensure the stability and functionality of the ultrafiltration membrane, special attention needs to be paid to the energy control during the welding process in the preparation process of the ultrafiltration centrifuge tube.

[0004] Currently, the preparation techniques of ultrafiltration centrifuge tubes usually adopt methods such as adhesive fixation, thermal welding or ultrasonic welding. However, these existing processes have certain limitations in practical applications. For example, in the traditional ultrasonic welding process, due to the wide range of acoustic energy transmission during welding, some energy may directly act on the ultrafiltration membrane, resulting in damage to the integrity of the ultrafiltration membrane pore size. This problem poses a hidden danger to the filtration accuracy and the reliability of biological sample processing, especially in applications involving high-precision separation. In addition, it may be difficult to balance the strength and sealing performance of the welding part, and problems such as cracking or leakage at the bonding point may occur during high-speed centrifugation, thus limiting the overall performance of the ultrafiltration centrifuge tube. Summary of the Invention

[0005] Aiming at the deficiencies of the prior art, the present invention provides a preparation process of a biological ultrafiltration centrifuge tube, which solves the problems that the pore size of the ultrafiltration membrane is easily damaged, the welding strength is insufficient and the sealing performance is difficult to balance during the welding process of the existing ultrafiltration centrifuge tubes.

[0006] To achieve the above objectives, the present invention is realized through the following technical solutions: A preparation process of a biological ultrafiltration centrifuge tube, comprising the following steps:

[0007] S1. Select an ultrafiltration membrane and cut it into a size that matches the inner bottom of the ultrafiltration centrifuge tube;

[0008] S2. Install the cut ultrafiltration membrane at the inner bottom of the ultrafiltration centrifuge tube and set it up through vacuum adsorption or mechanical fixture fixation;

[0009] S3. Check the flatness and tightness of the ultrafiltration membrane, and confirm the integrity of the membrane by using gas leakage test or liquid permeability test;

[0010] S4. Place the centrifuge tube with the installed ultrafiltration membrane at the transmitting end of the modified ultrasonic welding equipment;

[0011] S5. Start the welding equipment, and through the directionally transmitted ultrasonic energy, concentrate it on the welding part of the centrifuge tube for rapid welding;

[0012] S6. After welding, place the centrifuge tube sample in a normal temperature environment for natural cooling or use cold air flow for rapid cooling;

[0013] S7. After cooling, detect the pore size integrity of the ultrafiltration membrane and the sealing performance of the welding part.

[0014] Preferably, in step S4, the transmitting end of the ultrasonic welding equipment is modified in the following way:

[0015] Set multiple barrier films inside the ultrasonic transmitting horn, and form voids between the multiple barrier films for reflecting and canceling acoustic energy;

[0016] The barrier films are fixed inside the horn by adhesive inlay;

[0017] Calibrate the horn structure to ensure the concentration of acoustic energy in the welding area and avoid ultrasonic interference in non-welding areas.

[0018] Preferably, the barrier films are made of polyethylene material and PE material, with a thickness of 0.01 - 2 mm, and the edges of each layer of barrier film are fixed on the inner wall of the horn by adhesive process.

[0019] Preferably, the number of layers of the barrier films is 3 - 10 layers, and the void distance between the barrier films is 0.1 - 1 mm.

[0020] Preferably, in step S5, the acoustic wave frequency of the ultrasonic welding equipment is 20 - 40 kHz, and the power is 50 - 500 W.

[0021] Preferably, the acoustic energy is attenuated by the barrier films to less than 1% of the influence on the pore size of the ultrafiltration membrane.

[0022] Preferably, in step S7, detecting the welding quality includes the following steps:

[0023] Verify the airtightness of the welded part through a gas leakage test;

[0024] Use a high-speed centrifugal simulation experiment with a centrifugal speed of 10,000 - 12,000 rpm and a time of 3 - 30 min to verify the bonding strength of the welded part.

[0025] The present invention provides a preparation process for a biological ultrafiltration centrifuge tube. It has the following beneficial effects:

[0026] 1. By designing a multi-layer barrier film structure at the transmitting end of the ultrasonic welding equipment in the present invention, and using the reflection and attenuation mechanisms of sound waves, the energy impact of ultrasonic waves on non-welded areas is significantly reduced, avoiding the damage to the microporous structure of the ultrafiltration membrane during traditional welding, thereby realizing the protection of the structural integrity of the ultrafiltration membrane and ensuring that its functionality is not affected.

[0027] 2. The present invention adopts an improved directional ultrasonic welding technology, enabling the sound wave energy to act precisely on the welding area, forming high-strength welding joints, significantly improving the strength and airtightness of the welded part, ensuring the reliability of the ultrafiltration centrifuge tube under high-speed centrifugation and long-term use conditions, and at the same time avoiding the potential pollution risk brought by adhesives, improving the overall product performance and biological safety. Brief Description of the Drawings

[0028] Figure 1 It is a schematic diagram of the preparation steps of the present invention.

[0029] Figure 2 It is a schematic diagram of the structure of the transmitting end of the improved ultrasonic welding equipment of the present invention;

[0030] Figure 3 For Figure 2 An enlarged view of part A. Detailed Embodiments

[0031] The following will clearly and completely describe the technical solutions of the present invention in conjunction with the drawings of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0032] Embodiment:

[0033] Please refer to the attached Figure 1 drawings. The embodiment of the present invention provides a preparation process for a biological ultrafiltration centrifuge tube, including the following steps:

[0034] S1. Select an ultrafiltration membrane and cut the ultrafiltration membrane into a size matching the bottom of the inner wall of the ultrafiltration centrifuge tube;

[0035] S2. Install the ultrafiltration membrane at the bottom inner wall of the ultrafiltration centrifuge tube and ensure that the ultrafiltration membrane is evenly distributed;

[0036] Specifically, the ultrafiltration membrane is the core component of the ultrafiltration centrifuge tube, and its function is to efficiently filter biological samples through molecular-level pore sizes. To ensure the consistency of filtration performance and the integrity of the membrane pore size, first select ultrafiltration membrane materials with a specific pore size range (such as 0.01 - 0.1 microns) and excellent mechanical stability, such as polyethersulfone (PES), polyvinylidene fluoride (PVDF), or regenerated cellulose materials. Cut the ultrafiltration membrane into a circular or polygonal structure suitable for the bottom size of the centrifuge tube, and ensure that its edge is tightly combined with the inner wall of the centrifuge tube. The cut ultrafiltration membrane is fixed by mechanical clamps or vacuum adsorption to keep it flat during installation, avoiding wrinkles or damage. At the same time, use high-precision positioning equipment to install the membrane material in the center to ensure that its coverage completely matches the bottom of the centrifuge tube. To further ensure the uniform distribution of the membrane, an optical detection device can be used to detect the surface integrity and thickness uniformity of the membrane before installation, and membrane materials with pore defects or thickness deviations can be removed if necessary.

[0037] S3. Check the flatness and sealing of the ultrafiltration membrane, and use gas leakage testing or liquid permeability testing to confirm the integrity of the membrane;

[0038] Please refer to the appendix Figure 2 - appendix Figure 3 See, S4. Place the installed ultrafiltration centrifuge tube at the transmitting end of the modified ultrasonic welding equipment; the transmitting end of the ultrasonic welding equipment is modified through the following steps:

[0039] Inside the ultrasonic horn of the ultrasonic welding equipment, set multiple layers of barrier films. An air gap is formed between the multiple layers of barrier films to reflect and cancel the acoustic wave energy through the air gap. The barrier film is made of polyethylene material, the thickness of the barrier film is 0.01 - 2 mm, the number of layers of the barrier film is 3 - 10 layers, and the air gap distance between the barrier films is 0.1 - 1 mm.

[0040] Specifically, first, optimize the structure of the ultrasonic horn (HORN) of the ultrasonic welding equipment to ensure that its acoustic wave transmission meets the requirements of the welding process, and at the same time protect the ultrafiltration membrane structure inside the ultrafiltration centrifuge tube from damage. Install multiple layers of barrier films inside the ultrasonic horn. The material of the barrier film is selected as polyethylene (PE) with excellent barrier performance and mechanical stability, and its thickness range is controlled between 0.01 - 2 mm to reduce the additional influence on the ultrasonic wave propagation while ensuring the barrier performance.

[0041] The multi-layer design of the barrier film is evenly distributed inside the horn, and the number of layers is 3 - 10 layers. The specific number of layers can be adjusted according to the welding process parameters (such as acoustic wave frequency, power). A gap is set between the barrier films, and the gap distance is controlled within 0.1 - 1 mm to form multiple acoustic wave reflection and interference paths.

[0042] This design utilizes the multiple reflections and mutual cancellation effects of acoustic waves between different barrier films to effectively reduce the transmission of acoustic wave energy to non-welded areas, thereby protecting the ultrafiltration membrane at the bottom of the centrifuge tube from structural damage or pore size destruction caused by excessive acoustic wave intensity.

[0043] In specific operations, the barrier film is fixed to the wave guide surface inside the horn through a high-precision fixture to ensure uniform spacing between the film layers, while avoiding interference with the acoustic wave propagation path caused by film layer offset or sliding. After installation, the improved horn can be calibrated through acoustic wave energy distribution testing to ensure that the acoustic wave energy is concentrated in the welding area, while the acoustic wave intensity in the bottom area of the centrifuge tube is significantly attenuated. Through the above improvements, precise energy control of the welding part is achieved at the transmitting end of the ultrasonic welding equipment, effectively protecting the integrity of the ultrafiltration membrane while ensuring the welding strength.

[0044] S5. Start the welding equipment, and through the directionally transmitted ultrasonic energy, focus it on the welding part of the centrifuge tube for rapid welding; the acoustic wave frequency of the ultrasonic welding equipment is 20 - 40 kHz, and the power is 50 - 500 W.

[0045] Specifically, an improved ultrasonic welding equipment is used. After the acoustic wave energy is reflected and interfered by the barrier film multiple times, the energy is concentrated on the welding part of the ultrafiltration centrifuge tube. The working frequency of the ultrasonic welding equipment is set at 20 - 40 kHz, and the power range is 50 - 500 W. This parameter range has been optimized to minimize damage to the ultrafiltration membrane while ensuring welding quality.

[0046] During the welding process, the ultrasonic wave is transmitted to the top of the ultrafiltration centrifuge tube through the vibration of the horn, forming high-frequency vibration and local high temperature, causing the materials at the welding part to melt instantly and combine quickly, thus forming a high-strength welding point. During this process, after the acoustic wave is attenuated by the barrier film structure, its energy is effectively limited to the welding area, preventing the acoustic wave intensity from being too high and transmitting to the bottom of the centrifuge tube, ensuring that the ultrafiltration membrane is not damaged. At the same time, the directionally transmitted acoustic wave has high energy concentration, enabling a fast and uniform welding effect.

[0047] To ensure the stability of the welding process, during operation, the welding effect is further optimized by adjusting process parameters such as welding time, pressure, and acoustic wave power. After welding, the sealing performance and bonding strength of the welding part are detected to verify that it meets the stability requirements in the high-speed centrifugation use environment.

[0048] Through this step, ultrasonic welding can achieve efficient and precise welding of ultrafiltration centrifuge tubes, while ensuring that the structural integrity and pore functionality of the internal ultrafiltration membrane are not affected in any way.

[0049] S6. After welding is completed, place the centrifuge tube sample in a normal temperature environment for natural cooling or use a cold air flow for rapid cooling;

[0050] S7. After cooling is completed, detect the pore integrity of the ultrafiltration membrane and the sealing performance of the welding part. The acoustic energy is attenuated by the barrier film to less than 1% impact on the pore size of the ultrafiltration membrane.

[0051] Specifically, after welding is completed, place the centrifuge tube in a normal temperature environment for natural cooling or perform rapid cooling through a cold air flow to avoid affecting the material properties or causing deformation due to the continuous existence of high temperature at the welding part. During the cooling process, keep the overall structure of the centrifuge tube stable to prevent damage to the welding part or the ultrafiltration membrane due to stress concentration caused by rapid cooling.

[0052] After cooling is completed, first detect the pore integrity of the ultrafiltration membrane inside the centrifuge tube. Adopt gas flux test or liquid permeability test. By controlling the test pressure and flow rate, evaluate whether the pore size distribution of the ultrafiltration membrane is uniform to ensure that the acoustic energy during the welding process does not cause significant damage to the molecular-level pore size of the ultrafiltration membrane. The test results show that the acoustic energy attenuated by the barrier film has less than 1% impact on the pore size of the ultrafiltration membrane, meeting the design requirements.

[0053] Secondly, perform a sealing test on the welding part. Use a vacuum leak test or a pressure seal test to verify whether the sealing strength of the welding area meets the working requirements under high-speed centrifugation conditions, ensuring that the welding part will not leak or fall off under the action of centrifugal force. At the same time, observe the fusion quality and joint surface smoothness of the welding part through microscopic inspection of the welding area to confirm that there are no cracks, bubbles or other defects in the welding.

[0054] Through this step, further verify the structural integrity and functional stability of the ultrafiltration centrifuge tube, ensuring that it can provide efficient ultrafiltration performance and long-term reliability during actual use. This step is the final verification of the entire preparation process, ensuring the feasibility and applicability of the technical solution of the present invention.

[0055] Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A preparation process of a biological ultrafiltration centrifuge tube, characterized in that , including the following steps: S1, select an ultrafiltration membrane and cut the ultrafiltration membrane into a size that matches the bottom of the inner wall of the ultrafiltration centrifuge tube; S2, installing the cut ultrafiltration membrane on the bottom of the inner wall of the ultrafiltration centrifuge tube, and distributing and setting it by vacuum adsorption or mechanical clamp fixation; S3. Check the flatness and sealing of the ultrafiltration membrane, and confirm the integrity of the membrane using a gas leakage test or a liquid permeability test; S4, placing the centrifuge tube with the ultrafiltration membrane installed on the transmitting end of the improved ultrasonic welding equipment; S5, start the welding equipment, and use the ultrasonic energy transmitted in a direction to focus on the welding part of the centrifuge tube to perform rapid welding; S6. After welding is completed, place the centrifuge tube sample in a room temperature environment to cool naturally or use cold air flow for rapid cooling; S7. After cooling, check the pore integrity of the ultrafiltration membrane and the sealing performance of the welding parts.

2. The preparation process of a biological ultrafiltration centrifuge tube according to claim 1, characterized in that In the step S4, the transmitting end of the ultrasonic welding equipment is improved in the following ways: A multi-layer barrier film is arranged inside the ultrasonic transmitting horn, and gaps are formed between the multi-layer barrier films for reflecting and offsetting the sound wave energy; The barrier film is fixed to the inside of the speaker by a high-precision clamp; The horn structure is calibrated to ensure that the sound wave energy is concentrated in the welding area while avoiding ultrasonic interference in the non-welding area.

3. The preparation process of a biological ultrafiltration centrifuge tube according to claim 2, characterized in that The barrier film is made of polyethylene and PE materials with a thickness of 0.01-2mm. The edge of each layer of barrier film is fixed to the inner wall of the speaker through a hot melt process.

4. The preparation process of a biological ultrafiltration centrifuge tube according to claim 2, characterized in that: The number of layers of the barrier film is 3-10, and the gap distance between the barrier films is 0.1-1 mm.

5. The preparation process of a biological ultrafiltration centrifuge tube according to claim 1, characterized in that In the S5 step, the sound wave frequency of the ultrasonic welding equipment is 20-40kHz and the power is 50-500W.

6. The preparation process of a biological ultrafiltration centrifuge tube according to claim 2, characterized in that , the sound wave energy is attenuated by the barrier membrane to a level that affects the pore size of the ultrafiltration membrane by less than 1%.

7. The preparation process of a biological ultrafiltration centrifuge tube according to claim 1, characterized in that In the step S7, detecting welding quality includes the following steps: Verify the tightness of welding parts through gas leakage test; The bonding strength of the welding parts is verified by high-speed centrifugal simulation experiment with a centrifugal speed of 10000-12000rpm and a time of 3-30min.

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