Ultrafiltration centrifuge tube

Abstract

The utility model relates to the technical field of centrifugal tubes, in particular to an ultrafiltration centrifugal tube, which can be applied to a centrifugal machine and comprises an outer tube, an inner tube, an inner tube, an outer tube and an inner tube, and an opening at the top of the outer tube is connected with a plug cover through a connecting part; the top end or the bottom end of the inner pipe is inserted from the opening of the outer pipe, and the inner pipe stays and is inserted into the outer pipe; the inner tube is used for filtering and concentrating a sample injected into the inner tube, and a dead volume chamber is arranged at the bottom end of the inner tube; a supporting structure is arranged between the inner tube and the outer tube, so that a liquid retaining cavity is formed between the bottom end of the inner tube and the bottom end of the outer tube, and a concentrated sample is precipitated in the liquid retaining cavity. According to the utility model, the top end and the bottom end of the inner pipe can be respectively inserted into the outer pipe, namely, forward insertion and inverted insertion. The outer tube is provided with a supporting structure used for supporting the inner tube when the inner tube is inserted, and the inner tube is provided with a dead volume chamber used for preventing sample drying caused by excessive centrifugation and sample loss.

Description

TECHNICAL FIELD

[0001] The utility model relates to centrifugal tube technical field, concretely is a kind of ultrafiltration centrifugal tube. BACKGROUND

[0002] Ultrafiltration centrifugal tube is a kind of commonly used medical apparatus, and it is mainly used for the concentration and desalination of some liquid samples containing protein.The inner tube structure of the existing ultrafiltration centrifugal tube mainly has three kinds:

[0003] The first structure is to set filter structure in centrifugal tube, and the filter structure includes filter membrane and ultrafiltration membrane under filter membrane, and the typical structure such as the authorized announcement No.CN219615282U discloses the ultrafiltration tube structure for exosome extraction, sample is filtered through membrane, and the filtering and concentration effect is achieved, but the problem of this structure is that the area of membrane is small, the filtering efficiency is affected, there is no dead volume design, and sample is dried due to excessive centrifugation of sample, and sample is lost.

[0004] The second structure is to fix a layer of membrane in the designed frame, and the frame is sleeved in centrifugal tube, so as to achieve filtering effect under the action of centrifugal force.The defect of this structure is that centrifugal force is outward, and membrane and frame are bonded together, and the direction of centrifugal force is opposite, and the greater the centrifugal force, the greater the risk of leakage

[0005] The third structure is ultrasonic welding structure, and the ultrafiltration membrane is welded in the inner wall of centrifugal tube, and the ultrafiltration membrane and the inner wall of centrifugal tube are bonded in molten state after ultrasonic welding, and the ultrafiltration membrane is in the form of an open bag after bonding.Because the ultrafiltration membrane is extremely fragile, vibration can cause invisible damage to the ultrafiltration membrane, so that the filtering effect of actual product is affected. INVENTION CONTENTS

[0006] The utility model aims at providing an ultrafiltration centrifugal tube to solve the problems in the above background technology.

[0007] To achieve the above object, the utility model provides the following technical scheme:

[0008] An ultrafiltration centrifugal tube can be applied in centrifuge and comprises:

[0009] An outer tube is connected with a plug at the opening of the top of the outer tube through a connecting part;

[0010] An inner tube is inserted into the opening of the outer tube at the top end or bottom end and stays in the outer tube;

[0011] The inner tube filters and concentrates the sample added into the inner tube, and the bottom end of the inner tube has a dead volume chamber.

[0012] The inner tube and the outer tube have a support structure, so that a residual cavity is formed between the bottom end of the inner tube and the bottom end of the outer tube, and the sample after filtration and concentration is deposited in the residual cavity.

[0013] The residual cavity has an anti-backflow part for preventing the sample deposited in the residual cavity from flowing back.

[0014] Preferably, the dead volume chamber is 1 / 10 to 1 / 8 of the volume of the inner tube.

[0015] Preferably, the inner tube comprises a filter base and a filter membrane, the filter membrane is arranged on the filter base, the filter base comprises a sample inlet opening arranged at a first end of the filter base, a filter cavity in communication with the sample inlet opening, and a flow guide hole arranged on a second end of the filter base corresponding to the first end, and the dead volume chamber is located at the filter cavity close to the second end.

[0016] Preferably, the filter base is provided with a flow guide channel on the side close to the filter cavity, the flow guide hole penetrates through the filter base and is in communication with the flow guide channel, and the filter membrane is arranged between the filter base and the filter cavity and covers the flow guide channel and the flow guide hole, so as to filter the sample in the filter cavity.

[0017] Preferably, the support structure comprises an annular step in the outer tube, and the bottom of the inner tube has a protrusion, and the annular step is used for supporting the protrusion.

[0018] Preferably, the diameter of the inner tube is not less than the minimum inner diameter of the annular step.

[0019] Preferably, the annular step has an upward convex ring, and the top end and the bottom end of the inner tube have grooves which are fitted and assembled with the convex ring.

[0020] Preferably, the anti-backflow part comprises a baffle, the edge of the baffle is sealingly fixed to the inner wall of the residual cavity, and the middle part of the baffle has a cylindrical part with a flow channel, and the cylindrical part is provided with a permeation hole.

[0021] Preferably, the baffle is provided with an upper opening, and the opening is provided with an upwardly inclined sliding part, the sliding part is sealingly fixed to the inner wall of the residual cavity, and the opening is provided with a cavity below.

[0022] Preferably, the baffle is in the shape of "Ω" as a whole, the inner diameter of the opening is smaller than the inner diameter of the cavity, and the top of the cylindrical part is close to the opening.

[0023] Compared with the prior art, the present application has the following beneficial effects:

[0024] In this invention, the top and bottom of the inner tube can be inserted into the outer tube respectively, i.e., inserted upright and inverted. A "dead volume chamber" of approximately 40 μL is designed into the inner tube to prevent excessive centrifugation from drying out the sample and causing sample loss. The outer tube is designed with a support structure to support the inner tube during insertion. The inner tube can be centrifuged inverted positions. In practical applications, the sample volume after centrifugation is often very small and difficult to collect. Therefore, after a second centrifugation, the concentrated sample can be collected in the outer tube, facilitating collection and resulting in relatively better filtration.

[0025] This invention, through the anti-backflow part, especially the opening inner diameter being smaller than the cavity inner diameter and the top of the cylindrical part near the opening, can prevent / minimize the backflow of filtered liquid into the retention chamber or inner tube located above the baffle when the ultrafiltration centrifuge tube is in use, thus preventing it from affecting the filtration effect of the ultrafiltration centrifuge tube. Attached Figure Description

[0026] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0027] Figure 1 This is a schematic diagram of the structure in an exemplary embodiment of the present invention, in which the bottom end of the inner tube is inserted into the outer tube (positive insertion);

[0028] Figure 2 This utility model Figure 1 Vertical diagram;

[0029] Figure 3 This is a top view of an exemplary embodiment of the present invention;

[0030] Figure 4 This utility model Figure 1 The left view;

[0031] Figure 5 This is a schematic diagram of the preparation state in which the bottom end of the inner tube is inserted into the outer tube, which is an exemplary embodiment of the present invention.

[0032] Figure 6 This utility model Figure 5 Complete the insertion diagram;

[0033] Figure 7 This is a schematic diagram of the preparation state in which the top end of the inner tube is inserted into the outer tube (inverted insertion), which is an exemplary embodiment of the present invention.

[0034] Figure 8 This utility model Figure 7The state diagram in the process of insertion;

[0035] Figure 9 The outer tube structure schematic diagram of an exemplary embodiment of the present application;

[0036] Figure 10 The inner tube structure schematic diagram of an exemplary embodiment of the present application;

[0037] Figure 11 The present application Figure 10 The A-A section structure schematic diagram;

[0038] Figure 12 The filter base side view of an exemplary embodiment of the present application;

[0039] Figure 13 The present application Figure 10 The B-B section structure schematic diagram;

[0040] Figure 14 The top view of the present application Figure 12 ;

[0041] Figure 15 The vertical view of the present application Figure 12 ;

[0042] Figure 16 The outer tube another structure schematic diagram of an exemplary embodiment of the present application;

[0043] Figure 17 The inner tube another structure schematic diagram of an exemplary embodiment of the present application;

[0044] Figure 18 The present application Figure 16 Structure and Figure 17 Structure fitting insertion schematic diagram;

[0045] Figure 19 The anti-reflux part structure schematic diagram of the present application.

[0046] In the figure: 1-outer tube, 2-inner tube, 3-filter membrane, 4-annular step, 5-plug, 6-connection part, 7-dead volume chamber, 8-flow guide hole, 9-protrusion, 10-filter base, 11-liquid retention cavity, 12-sample inlet opening, 13-filtering cavity, 14-flow guide channel, 15-convex ring, 16-groove, 17-anti-reflux part, 18-flap, 19-cylindrical part, 20-opening, 21-cavity, 22-permeation hole, 23-slipping part, 24-flow channel. DETAILED DESCRIPTION

[0047] The technical solutions in the embodiments of the present application will be clearly and completely described with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. The description of the at least one exemplary embodiment is merely illustrative in nature and in no way should be construed as any limitation on the present application and its applications or uses. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor fall within the scope of the present application.

[0048] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the example embodiments according to the present application. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and / or "comprising," when used in this specification, specify the presence of stated features, steps, operations, elements, components, and / or groups thereof, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and / or groups thereof.

[0049] The relative arrangement of components and steps, numerical expressions, and numerical values set forth in the embodiments are not intended to limit the scope of the present application unless specifically stated otherwise. At the same time, it should be understood that the sizes of the various parts shown in the drawings are not drawn in proportion to the actual proportions. The techniques, methods and devices known to those of ordinary skill in the relevant art can not be discussed in detail, but should be considered as part of the authorized description. In all examples shown and discussed herein, any specific value should be interpreted as merely exemplary, and not as a limitation. Therefore, other examples of the example embodiments can have different values. It should be noted that similar reference numbers and letters represent similar items in the following drawings, so further discussion is not necessary once an item is defined in one drawing.

[0050] In the description of the present application, it should be understood that the orientation words such as "front, rear, upper, lower, left, right", "horizontal, vertical, perpendicular, horizontal" and "top, bottom" and the like indicate the orientation or positional relationship shown in the drawings, which is only for the convenience of describing the present application and simplifying the description, and does not indicate and imply that the indicated device or element must have a particular orientation or be constructed and operated in a particular orientation, therefore it cannot be understood as a limitation on the scope of protection of the present application; the orientation words "inner, outer" refer to the inner and outer of the contour of each component itself.

[0051] For purposes of the description hereinafter, spatial relations terms, such as "above", "below", "top", "bottom", "side", "higher", "lower", "upper", "lower", "horizontal", "vertical", "front", "back", "rear", "up", "down", and the like, can be used herein for describing the spatial relationship between one device or feature to another device or feature as illustrated in the figures. It is to be understood that the spatial relations terms are intended to encompass different orientations of the device in use or operation in addition to the orientations depicted in the figures. For example, if a device in the figures is inverted, then a device described as "above" or "up" other devices or structures can be oriented "below" or "down" the other devices or structures. Accordingly, the exemplary terms "above" and "below" can encompass both orientations "above" and "below". The devices can also be oriented in other ways (rotated 90 degrees or at other orientations) and the spatial relationship terms are to be interpreted accordingly.

[0052] In addition, it should be noted that the use of "first", "second", and the like words of distinction do not have a special meaning, and are only used to distinguish corresponding parts, and therefore cannot be understood as limiting the scope of protection of the utility model.

[0053] Please refer to Figures 1 to 19 The utility model provides a technical scheme:

[0054] A kind of ultrafiltration centrifugal tube, the ultrafiltration centrifugal tube can be applied to centrifuge, the ultrafiltration centrifugal tube can be used to separate biological substances such as antibody enzyme, nucleic acid and protein, for the purpose of concentration, desalination, purification and fractionation, such as concentrated material (concentrated liquid is specifically explained below) such as concentrated urine, serum, plasma and cerebrospinal fluid separation collection, and the ultrafiltration centrifugal tube includes:

[0055] The outer tube 1 is connected with the plug cover 5 at the opening of the top by the connecting part 6;

[0056] The inner tube 2 is inserted into the opening of the outer tube 1 by the top end or bottom end and stays inserted in the outer tube 1;

[0057] The inner tube 2 filters and concentrates the sample filled into the inner tube 2, and the bottom end of the inner tube 2 has a dead volume chamber 7;

[0058] The inner tube 2 and the outer tube 1 have a support structure, so that the inner tube 2 and the outer tube 1 have a residual cavity 11 between the bottom end of the inner tube 2 and the bottom end of the outer tube 1, and the concentrated sample is precipitated in the residual cavity 11;

[0059] The residual cavity 11 has an anti-backflow part 17 for preventing the sample precipitated in the residual cavity 11 from flowing back.

[0060] In a specific embodiment, as Figure 1As shown, the dead volume chamber 7 is one-tenth to one-eighth of the volume of the inner tube 2. The inner tube 2 is designed with a "dead volume chamber" of about 40ul, which prevents the sample from drying out due to excessive centrifugation, resulting in loss of the sample.

[0061] In a specific embodiment, as shown in Figure 4 、 Figures 10 to 15 The inner tube 2 includes a filter base 10 and a filter membrane 3, the filter membrane 3 is arranged on the filter base 10, the filter base 10 includes a sample inlet opening 12 arranged at the first end of the filter base 10, a filter cavity 13 in communication with the sample inlet opening 12, a flow guide hole 8 arranged on the second end of the filter base 10 corresponding to the first end, the dead volume chamber 7 is located at the second end of the filter cavity 13, the filter base 10 is provided with a flow guide channel 14 on the side close to the filter cavity 13, the flow guide hole 8 penetrates through the filter base 10 and is in communication with the flow guide channel 14, and the filter membrane 3 is arranged between the filter base 10 and the filter cavity 13 and covers the flow guide channel 14 and the flow guide hole 8, so as to filter the sample in the filter cavity 13.

[0062] The filter membrane 3 is an ultrafiltration membrane. The volume between the hole 8 at the bottom of the filter membrane 3 and the bottom of the inner tube 2 is the dead volume chamber 7. When the ultrafiltration centrifuge tube is centrifuged, the sample added to the inner tube 2 passes through the filter membrane 3, which is used to trap small particles in the sample added to the inner tube 2. The sample passes through the filter membrane 3 to achieve the effect of filtration and concentration.

[0063] The inner tube 2 is used for the filtration and centrifugal separation of the sample liquid to be filtered, and the outer tube 1 (of the supernatant cavity 11) is used for the collection of the filtered filtrate or concentrated liquid (such as concentrated urine). The sample (or sample liquid) can enter the filter cavity 13 from the sample inlet opening 12 and be filtered by the filter membrane 13 to form a filtrate, and the filtrate can be drained from the filter cavity 13 through the flow guide hole 8, and the unfiltered sample liquid (hereinafter referred to as concentrated liquid) is retained in the dead volume chamber 7. The filter base 10 is a three-dimensional shell with one end open and the other end closed, preferably a hollow cylinder.

[0064] In use, the inner tube 2 is inserted into the outer tube 1 from the opening of the outer tube 1. When the sample liquid is separated and filtered, the filtered filtrate can be guided from the flow guide hole 8 to the outer tube 1 after the sample liquid is filtered by the filter membrane 3, and the concentrated liquid is accumulated in the dead volume chamber 7. The inner tube 2 is detached from the outer tube 1, and the concentrated liquid in the dead volume chamber 7 is transferred to other experimental containers (such as test tubes) for storage, achieving different experimental purposes. The plug 5 is used for sealing and storage to avoid waste and pollution. The opening of the outer tube 1 can be provided with external threads, which are threadedly connected with the cover body provided with internal threads, or the opening of the outer tube 1 is provided with the plug 5, which is inserted into the opening to achieve sealing and storage.

[0065] The sample liquid can be filtered through the filter membrane 3, drained from the flow guide channel 14 to the flow guide hole 8, and then discharged to the residual liquid cavity 11 through the flow guide hole 8, so that the filtrate is collected.

[0066] The flow guide channel 14 comprises a plurality of flow guide grooves, which are uniformly distributed on the side of the filter base 10 close to the filter membrane 3 and extend along the axial direction of the filter base 10 (the direction of the line connecting the first end center point and the second end center point). The flow guide groove is connected with at least one flow guide hole 8, so as to guide the centrifugal filtrate to the residual liquid cavity 11, thereby avoiding liquid leakage.

[0067] Preferably, the flow guide hole 8 is arranged in one-to-one correspondence with the flow guide groove, for example, Figure 13 In the embodiment, four flow guide holes 8 and flow guide grooves are arranged on each side.

[0068] In a specific embodiment, as shown in Figure 2 , Figures 8 to 9 The outer tube 1 is designed to have a support structure, which comprises an annular step 4 in the inner tube 2. The bottom of the inner tube 2 has a protrusion 9, and the annular step 4 is used to support the protrusion 9. After the completion of the normal insertion, the protrusion 9 at the bottom end of the inner tube 2 is located in the annular step 4, and the annular step 4 supports the protrusion 9. At this time, it indicates that the inner tube 2 is inserted into the outer tube 1.

[0069] In a specific embodiment, as shown in Figure 5 The diameter of the inner tube 2 is not less than the minimum inner diameter of the annular step 4. When the inner tube 2 is inserted in reverse, the top end of the inner tube 2 is inserted into the outer tube 1. When the top end of the inner tube 2 contacts the annular step 4, the annular step 4 supports the top end of the inner tube 2. At this time, it indicates that the inner tube 2 is inserted into the outer tube 1 in reverse.

[0070] The utility model discloses, the top end and the bottom end of inner tube 2 can be inserted into outer tube 1 respectively, i. e. normal insertion and reverse insertion. After completing insertion, the opening of outer tube 1 is covered by plug cover 5, so that inner tube 1 is pressed in outer tube 1 to form centrifugal tube. In this way, the centrifugal tube can be placed in the centrifugal machine for centrifugal operation.

[0071] The utility model discloses, as shown in Figures 16-18 The annular step 4 has an upward protruding ring 15, and the top end and the bottom end of the inner tube 2 have a groove 16 that is adapted to be inserted with the protruding ring 15. By adapting the insertion of the protruding ring 15 and the groove 16, the mutual friction force of the protruding ring 15 and the groove 16 can be utilized to achieve the quick relative fixation of the two after the normal insertion or reverse insertion of the inner tube 2 is completed. In this way, during centrifugation, the relative rotation of the two can be reduced, thereby assisting the plug cover 5 in fixing the inner tube 2 and the outer tube 1.

[0072] This utility model features a design characteristic: the ultrafiltration tube is designed with a "dead volume chamber," specifically, a "dead volume chamber" is reserved inside / at the bottom of the inner tube 2. The dead volume chamber 7 is approximately 40 μL. Excessive centrifugation can cause the sample to dry out, leading to sample loss. Figure 1 As shown, the dead volume chamber 7 is the volume / capacity of the part below the guide hole 8 (bottom of the inner tube 2). Figures 5 to 8 As shown, the outer tube 1 is designed with a support structure, and the inner tube 2 can be inverted for centrifugation. In actual application, the sample volume after centrifugation is very small and difficult to collect. Therefore, after centrifugation again, the concentrated sample can be collected in the outer tube 1 (the retention chamber 11), which is convenient for collection. Coating process: Through mold structure design, the ultrafiltration centrifuge tube product of this utility model is integrally formed. The plastic part (inner tube 2) with the welded filter membrane 3 is coated with thermoplastic to form an integral structure.

[0073] When using this utility model:

[0074] 1. Insert the inner tube 2 into the outer tube 1 to form a centrifuge tube, and then add the liquid sample into the inner tube 2;

[0075] 2. Place the centrifuge tubes in a centrifuge and centrifuge at 12000g for 20 minutes at room temperature;

[0076] 3. Remove the centrifuge tube and replace it with a new outer tube 1. At this time, there is a small amount of concentrated liquid at the bottom of the inner tube 2. Invert the inner tube 2 and insert it into the outer tube 1 to centrifuge again. The concentrated liquid will go to the bottom of the outer tube 1 and then be collected for subsequent testing.

[0077] The filter membrane 3 is used for filtration. It is welded to the side notch 10 of the inner tube 2. The concentrated sample can be collected in the outer tube 1 through the filter membrane 3.

[0078] In one specific embodiment, such as Figures 18-19 As shown, the retention chamber 11 has an anti-backflow section 17 to prevent the backflow of samples that have settled in the retention chamber 11. The anti-backflow section 17 is located slightly below the annular step 4 of the supporting structure and has a certain distance from the top and bottom of the inner tube 2 to prevent contact with the dead volume chamber 7. It includes a baffle 18, the edge of which is sealed and fixed to the inner wall of the retention chamber 11. The baffle 18 has a cylindrical part 19 with a flow channel 24 in the middle and a permeation hole 22 on the cylindrical part 19. The baffle 18 has an opening 20 at the top and an upwardly inclined sliding part 23 at the opening 20. The sliding part 23 is sealed and fixed to the inner wall of the retention chamber 11. There is a cavity 21 below the opening 20. The baffle 18 is generally Ω-shaped. The inner diameter of the opening 20 is smaller than the inner diameter of the cavity 21. The top of the cylindrical part 19 is close to the opening 20.

[0079] The slide portion 23 and the cylindrical portion 19 are parts of the baffle 18, and the slide portion 23 is inclined, i.e. the top portion is inclined downward, so that the filtrate formed by filtering the filter membrane 13 can quickly slide into the cavity 21. The filtrate enters the cavity 21, and then passes through the permeation hole 22 and the flow channel 24 to fall into the retentate cavity 11 below the baffle 18 during centrifugation.

[0080] By the anti-backflow portion 17, especially the inner diameter of the opening 20 is smaller than the inner diameter of the cavity 21, and the top portion of the cylindrical portion 19 is close to the opening 20, the baffle 18 can block / try to reduce the backflow of the filtered liquid to the retentate cavity 11 above the baffle 18 or the inner tube 2 during use of the ultrafiltration centrifugal tube, so as to prevent the filtration effect of the ultrafiltration centrifugal tube from being affected.

[0081] The slide portion 23 is inclined, and the inner diameter of the opening 20 is smaller than the inner diameter of the cavity 21, so that the filtrate below the filter membrane 13 is quickly transferred to the retentate cavity 11 below the baffle 18, so as to improve the efficiency of the dead volume chamber 7 in concentrating the filtrate.

[0082] The material of the baffle 18 can be medical silica gel or PET; or the same as the materials of the outer tube 1 and the inner tube 2, which can be determined according to actual use.

[0083] The part not described in the utility model is the prior art.

[0084] The above is only a preferred specific embodiment of the utility model, but the protection scope of the utility model is not limited to this. Any person skilled in the art can make equivalent replacement or change according to the technical scheme and the inventive concept of the utility model within the technical range disclosed by the utility model, which should be covered in the protection scope of the utility model.

Claims

1. An ultrafiltration centrifuge tube, characterized in that, The ultrafiltration centrifugal tube can be applied in a centrifuge and comprises: an outer tube (1) having a plug (5) connected to the opening at the top of the outer tube (1) through a connecting part (6); an inner tube (2) inserted into the opening of the outer tube (1) at the top or bottom end and staying in the outer tube (1); the inner tube (2) filters and concentrates the sample added into the inner tube (2), and the bottom end of the inner tube (2) has a dead volume chamber (7); the inner tube (2) and the outer tube (1) have a supporting structure, so that there is a residual cavity (11) between the bottom end of the inner tube (2) and the bottom end of the outer tube (1), and the sample after filtration and concentration is deposited in the residual cavity (11); the residual cavity (11) has an anti-backflow part (17) for preventing the sample deposited in the residual cavity (11) from flowing back.

2. The ultrafiltration centrifuge tube of claim 1, wherein, The dead volume chamber (7) is one-tenth to one-eighth of the volume of the inner tube (2).

3. The ultrafiltration centrifuge tube of claim 1, wherein, The inner tube (2) comprises a filter base (10) and a filter membrane (3), the filter membrane (3) is arranged on the filter base (10), the filter base (10) comprises a sample inlet opening (12) arranged at the first end of the filter base (10), a filter cavity (13) in communication with the sample inlet opening (12), a flow guide hole (8) arranged at the second end of the filter base (10) corresponding to the first end, and the dead volume chamber (7) is located at the filter cavity (13) close to the second end.

4. The ultrafiltration centrifuge tube of claim 3, wherein, The filter base (10) is provided with a flow guide channel (14) on the side close to the filter cavity (13), the flow guide hole (8) penetrates through the filter base (10) and is in communication with the flow guide channel (14), and the filter membrane (3) is arranged between the filter base (10) and the filter cavity (13) and covers the flow guide channel (14) and the flow guide hole (8) to filter the sample in the filter cavity (13).

5. The ultrafiltration centrifuge tube of claim 3, wherein, The supporting structure comprises an annular step (4) in the outer tube (1), and the bottom of the inner tube (2) has a protrusion (9), and the annular step (4) is used to support the protrusion (9).

6. The ultrafiltration centrifuge tube of claim 5, wherein, The diameter of the inner tube (2) is not less than the minimum inner diameter of the annular step (4).

7. The ultrafiltration centrifuge tube of claim 5, wherein, The annular step (4) has an upward convex ring (15), and the top end and the bottom end of the inner tube (2) have a groove (16) that is fitted and assembled with the convex ring (15).

8. The ultrafiltration centrifuge tube of claim 1, wherein, The anti-backflow part (17) comprises a baffle (18), the edge of the baffle (18) is sealingly fixed in the inner wall of the residual cavity (11), the middle part of the baffle (18) has a cylindrical part (19) with a flow channel (24), and the cylindrical part (19) has a permeation hole (22).

9. The ultrafiltration centrifuge tube of claim 8, wherein, The upper part of the baffle (18) is provided with an opening (20), and the opening (20) has an upward inclined sliding part (23), the sliding part (23) is sealingly fixed with the inner wall of the residual cavity (11), and the opening (20) has a cavity (21) below.

10. The ultrafiltration centrifuge tube of claim 9, wherein, The baffle (18) is in the shape of "Ω", the inner diameter of the opening (20) is smaller than the inner diameter of the cavity (21), and the top of the cylindrical part (19) is close to the opening (20).

Images