A centrifuge adapter assembly for PRP preparation

Abstract

The utility model discloses a centrifugal adapter assembly for PRP preparation, which comprises a detachable adapter cup and a supporting buffer frame. The adapter cup is inserted into the centrifugal cup of a centrifuge. The inner bottom surface of the adapter cup is provided with a first step surface and a second step surface arranged in sequence. The first step surface supports the broken section of the piston rod after being broken. The second step surface with a smaller diameter supports the luer cap. The inner wall surface of the supporting buffer frame is in interference fit with the outer wall surface of the needle tube of the catheter flusher. The two ends of the supporting buffer frame are provided with a slot for accommodating the finger rest end. The end surface of the supporting buffer frame corresponding to the annular support platform abuts against the upper end surface of the annular support platform. The catheter flusher is loaded into the annular support platform with the finger rest end or the pointed end facing the annular support platform, forming the first or second mounting position. The utility model improves the pipe wall stiffness and inhibits deformation by interference holding. The same step surface is compatible with two loading orientations, so that the axial load is shared by the needle tube end and the end surface of the supporting buffer frame, avoiding stress concentration.

Description

Technical Field

[0001] This utility model relates to the field of biomedical device technology, and more specifically, to a centrifuge adapter assembly for PRP preparation. Background Technology

[0002] Platelet-rich plasma (PRP), a commonly used material for repair and treatment in the biomedical field, relies heavily on centrifugation technology to separate blood components during its preparation. Currently, the mainstream method in the industry is a two-step centrifugation process for PRP preparation. The general procedure is as follows: first, centrifugation at a low speed to settle and remove red blood cells; then, centrifugation at a slightly higher speed to further concentrate and enrich platelets. Both centrifugation steps can usually be completed on a conventional low-speed centrifuge. In recent years, to reduce the repeated transfer of blood samples between containers, the industry has begun to use disposable catheter flushing devices and other syringe-like instruments as centrifuge carriers, integrating collection, centrifugation, and sampling into a single device. Various centrifugation adapter structures have been developed for this purpose.

[0003] However, existing centrifugal adapter structures still have many problems that need to be solved in practical applications, specifically in the following aspects:

[0004] One prominent issue is the lack of support for the syringe barrel under centrifugal loads, resulting in insufficient geometric stability. Chinese utility model patent CN215901985U discloses a centrifuge for PRP preparation. The centrifuge sleeve has a fixed base and coupling column at the bottom of its receiving cavity to axially position the plunger at the lower end of the syringe. A threaded sealing cap at the upper end of the sleeve presses against the syringe end seal, thus fixing the syringe inside the sleeve with the plunger end facing the bottom of the sleeve for direct centrifugation. This design concentrates the fixing effect on the two ends of the syringe; there is no dedicated support design between the inner wall of the sleeve and the side wall of the syringe barrel, leaving the middle section of the syringe barrel essentially suspended. Disposable syringes are typically designed for axial injection, resulting in thinner walls. Under radial loads in a centrifugal force field, the wall can only resist deformation through its own stiffness, making it prone to radial expansion, ellipticization, local bending, and even cracking. In a comparative test using commercially available disposable syringe carrier adapters for low-speed PRP centrifugation, the applicant observed severe and mild leakage in the two syringes, respectively, revealing a problem with the tubing walls not being effectively protected during centrifugation. Once the tubing walls deform, the geometric boundaries of blood stratification change, causing shifts in the height of the erythrocyte column, the position of the white membrane layer, and the apparent volume of the target layer, making it difficult to reliably reproduce the sampling endpoint.

[0005] Secondly, the two loading orientations, upright and inverted, are difficult to reconcile with a single structural design. In clinical practice, different PRP preparation scenarios have specific requirements for the loading orientation of syringe carriers: some scenarios require the tip to face upwards so that the supernatant plasma can be drawn from that end after centrifugation; others require the tip to face downwards so that the settled red blood cells can be expelled from that end after centrifugation. However, the structures at both ends of the syringe differ significantly: one end is a small tip with a Luer cap, while the other end refers to the broken section left after the support end and piston rod are broken off. The two ends have different dimensions, load-bearing area, and protrusion height. Most existing centrifuge adapter structures are designed with a single, fixed syringe orientation. For example, CN215901985U uses a coupling column at the bottom of the receiving chamber and a locking head inside the upper sealing cap, respectively, for the plunger and end seal. The syringe can only be fixed inside the cannula with the plunger end facing the bottom of the cannula. Different operating modes are achieved by placing the entire centrifuge cannula forward or backward, without changing the syringe's orientation relative to the cannula. If the syringe's orientation needs to be reversed within the same cannula, there is no corresponding support or clearance structure available. If a change in preparation process is required, the entire adapter clamp must often be replaced, increasing the medical institution's consumable procurement costs, requiring additional clamp cleaning and verification, and also increasing the risk of sample contamination due to operational errors during replacement.

[0006] Third, the axial load is concentrated at a single end, making the end susceptible to damage due to excessive local stress. Existing centrifuge adapter structures generally employ only one method for axial restraint: either relying on a two-point clamping mechanism, such as the upper threaded sealing cap pressing against the lower coupling column (as described in CN215901985U), or relying on pins or clamps to hold the piston, or relying on a flip-cap latch engaging with a bottom hole. All of these methods concentrate the axial load during centrifugation on a single end or a localized area of ​​the apparatus. The limited bearing area at the end makes it prone to deformation of the sealing end, loosening of the Luer cap, or passive displacement of the piston during prolonged or high-speed centrifugation, leading to sample spillage and disturbance of the stratification interface.

[0007] Therefore, how to provide a new centrifuge adapter assembly for PRP preparation that provides effective radial support for the needle tube wall during centrifugation, and is compatible with both upright and inverted loading orientations with the same structure, so that the axial load is not concentrated on a single end, is a problem that urgently needs to be solved by those skilled in the art. Utility Model Content

[0008] In view of this, the present invention provides a centrifugal adapter assembly for PRP preparation, which aims to solve the technical problems of the existing adapter structure lacking support for the syringe barrel, insufficient geometric stability of the tube wall under centrifugal load, and requiring the replacement of the entire adapter structure for both upright and inverted loading orientations, and axial load being concentrated at a single end.

[0009] To achieve the above objectives, the present invention adopts the following technical solution: A centrifuge adapter assembly for PRP preparation is provided for use with a catheter flushing device. The catheter flushing device has a needle, finger supports and a tip at both ends of the needle, a Luer cap mounted on the tip, a piston inside the needle, and a piston rod connected to the piston. The piston rod can be broken off from a pre-cut point, and after breaking off, a section connected to the piston is retained, with the broken end of this section being a cross-section. The centrifuge adapter assembly includes an adapter cup and a support buffer. The adapter cup is used to be inserted into the centrifuge cup. The inner bottom surface of the adapter cup is provided with an annular support platform. The inner wall surface of the annular support platform is formed with a stepped surface. The stepped surface includes a first stepped surface and a second stepped surface arranged sequentially along the axial direction of the adapter cup. The support buffer is detachably inserted into the adapter cup. The inner wall of the support buffer is used for interference fit with the outer wall of the syringe. The two ends of the support buffer have relief slots on the side of the syringe to accommodate the finger support end. The end face of the support buffer corresponding to the annular support platform abuts against the upper end of the annular support platform. The centrifuge adapter assembly has a first mounting position and a second mounting position for inserting either the finger support end or the tip of the tubing flusher into the adapter cup; in the first mounting position, a first stepped surface is used to abut against the cross section, and a relief slot at one end of the support buffer corresponding to the annular support platform is used to accommodate the finger support end; in the second mounting position, a second stepped surface is used to abut against the Luer cap.

[0010] Therefore, this invention utilizes the interference fit between the inner wall of the support buffer and the outer wall of the syringe to create a radially enveloping grip on the syringe wall, thus superimposing the rigidity of the support buffer onto the thin-walled syringe body. The rigidity of the support buffer is formed by its structure: the cylindrical body, the support plate extending axially along the cylindrical body, and the support rings arranged circumferentially along the cylindrical body form a rigid skeleton, with the inner support ribs extending axially along the inner wall of the cylindrical body transmitting the rigidity of this skeleton to the contact point with the syringe. It is also formed by its material, being made of rigid engineering plastics such as medical-grade polycarbonate and polysulfone, or metals. Therefore, the syringe wall no longer relies solely on its own rigidity to resist radial loads in a centrifugal force field. Meanwhile, this invention concentrates the structure supporting the two different ends of the conduit flusher onto the same stepped surface on the inner wall of the annular support platform: the larger diameter first stepped surface supports the broken section of the piston rod, and the smaller diameter second stepped surface supports the Luer cap; the two stepped surfaces are arranged sequentially along the axial direction. Therefore, regardless of whether the conduit flusher is installed with the finger support end or the tip facing the annular support platform, it is supported by the same set of supporting structures, and no parts need to be changed for both upright and inverted loading orientations. In both installation positions, the axial load is simultaneously borne by the support section at one end of the annular support platform corresponding to the end of the support buffer frame, and the end is not subjected to independent pressure. This solves the problems of lack of support for the pipe wall, the need to change parts when changing orientations, and single-point load bearing at the end, achieving stable pipe wall, bidirectional compatibility, and distributed load bearing in PRP centrifugal preparation.

[0011] Preferably, in the above-mentioned centrifugal adapter assembly for PRP preparation, the support buffer frame includes a cylinder, a support plate, and a support ring. The inner wall of the cylinder is provided with internal support ribs extending axially along the cylinder. There are multiple internal support ribs, which are arranged at intervals along the circumference of the cylinder. The top surface of each internal support rib is used for interference fit with the outer wall surface of the syringe. The support plate extends axially along the cylinder and is fixedly connected to the outer wall surface of the cylinder. The support ring is arranged circumferentially along the cylinder and is fixedly connected to the support plate. The outer edge of the support plate is arranged correspondingly to and inserted into the inner wall surface of the adapter cup. The two ends of the support plate along the axial direction of the cylinder are flush with the cylinder and extend axially along the radial outer side of the cylinder to form a support section. The support section abuts against the upper end surface of the annular support platform. The inner side of the support section forms a clearance groove with the end face of the cylinder.

[0012] Preferably, in the above-mentioned centrifugal adapter assembly for PRP preparation, the groove wall surface of the clearance slot is arranged at a distance from the outer edge of the finger support end.

[0013] Preferably, in the above-mentioned centrifugal adapter assembly for PRP preparation, there are four support plates, which are arranged in a uniform array along the circumference of the cylinder.

[0014] Preferably, in the above-mentioned centrifugal adapter assembly for PRP preparation, there are four internal support ribs, which are arranged in a uniform array along the circumference of the cylinder, and each internal support rib extends along the axial direction of the cylinder to both ends of the cylinder.

[0015] Preferably, in the above-mentioned centrifugal adapter assembly for PRP preparation, the cross-section of the inner support rib is rectangular, trapezoidal, or an arc shape with one side rounded off from the inner wall of the cylinder.

[0016] Preferably, in the above-mentioned centrifugal adapter assembly for PRP preparation, the diameter of the virtual envelope formed by the top surfaces of the multiple inner support ribs is smaller than the outer diameter of the needle tube, and the difference between the two is 0.2 mm to 0.6 mm.

[0017] Preferably, in the above-mentioned centrifugal adapter assembly for PRP preparation, the diameter of the first step surface is larger than the diameter of the second step surface, and the first step surface is closer to the opening of the adapter cup than the second step surface; the portion of the inner wall of the annular support platform surrounding the first step surface is arranged to correspond to the outer periphery of the cross section, and the portion surrounding the second step surface is arranged to correspond to the outer wall of the Luer cap.

[0018] Preferably, in the above-mentioned centrifugal adapter assembly for PRP preparation, the outer wall surface of the adapter cup is provided with reinforcing ribs, and multiple reinforcing ribs are arranged along the circumference and axial direction of the adapter cup and form a hollow gap with each other.

[0019] Preferably, in the centrifuge adapter assembly for PRP preparation described above, the support buffer frame is made of a transparent or semi-transparent material, which is polycarbonate or polysulfone.

[0020] As can be seen from the above technical solution, compared with the prior art, this utility model provides a centrifuge adapter assembly for PRP preparation, which has the following beneficial effects: It improves the rigidity of the tube wall; the support buffer frame is interference-fitted with the outer wall of the tube along the tube body, superimposing the rigidity of the support buffer frame onto the thin-walled tube body. In the centrifugal force field, the tube wall no longer relies solely on its own rigidity to resist radial loads, thus reducing the risk of radial expansion, ellipticization, and local bending. The geometric boundaries of blood stratification, the height of the erythrocyte column, and the position of the target layer are more stable, which is beneficial for the repeatability of the sampling endpoint; it is bidirectionally compatible without component replacement; the first and second step surfaces of the same step surface respectively support the broken section of the piston rod and the Luer cap, and the support buffer frame symmetrically yields at both ends. The slotted design allows the finger support end to have space to rest in either orientation. Both upright and inverted loading orientations share the same support structure, eliminating the need to replace the adapter cup or support buffer when switching preparation modes, reducing consumable costs and cleaning / validation workload. Axial load is distributed; in both mounting positions, the axial load is simultaneously borne by the end and the support buffer facing the annular support platform, preventing the end from being individually locked. This reduces localized stress at the sealing end, decreasing the risk of Luer cap loosening and piston passive displacement. Samples do not need to be transferred to adapt to the centrifuge; whole blood is collected, centrifuged, and stratified within the catheter flusher, eliminating the need to transfer to dedicated centrifuge tubes. This reduces bacterial contamination and plasma residue loss caused by opening caps and pipetting, helping to ensure the final PRP concentration. Furthermore, the adapter cup can be packaged in disposable aseptic packaging, forming a sterile barrier between the catheter flusher and the centrifuge cup, reducing the risk of cross-contamination and simplifying aseptic procedures. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 A cross-sectional view of the centrifuge adapter assembly for PRP preparation provided by this utility model in the second mounting position; Figure 2 for Figure 1 Enlarged view of point A in the middle; Figure 3 A cross-sectional view of the centrifuge adapter assembly for PRP preparation provided by this utility model in the first mounting position; Figure 4 for Figure 3 Enlarged view of point B in the middle; Figure 5A schematic diagram of the catheter flushing device used in conjunction with this utility model; Figure 6 A cross-sectional view of the adapter cup provided by this utility model; Figure 7 for Figure 6 Enlarged view of point C in the middle; Figure 8 A schematic diagram of the support buffer frame provided by this utility model.

[0023] in: 1-Catheter flushing device; 2-Luer cap; 3-Adaptor cup; 4-Support buffer frame; 11-Needle; 12-Piston; 13-Piston rod; 31-Annular support platform; 32-Reinforcing rib; 41-Cylinder; 42-Inner support rib; 43-Support plate; 44-Support ring; 45-Relief groove; 111-Finger support end; 112-Tip; 131-Pre-break; 311-Step surface; 3111-First step surface; 3112-Second step surface. Detailed Implementation

[0024] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0025] See Figures 1 to 8 This utility model discloses a centrifuge adapter assembly for PRP preparation. The assembly includes a separable adapter cup 3 and a support buffer frame 4, with the support buffer frame 4 inserted into the adapter cup 3. As a complementary component, a catheter flushing device 1 includes a needle 11, a piston 12, and a piston rod 13. The needle 11 has a finger support end 111 and a tip 112. The piston rod 13 has a pre-cut end 131 near the piston 12, and a Luer cap 2 is installed on the tip 112.

[0026] The outer wall of the adapter cup 3 is arranged and inserted into the inner wall of the centrifuge cup. The inner bottom surface of the adapter cup 3 is provided with an annular support platform 31. The inner wall surface of the annular support platform 31 forms a stepped surface 311. The stepped surface 311 includes a first stepped surface 3111 and a second stepped surface 3112 arranged sequentially along the axial direction of the annular support platform 31. The diameter of the first stepped surface 3111 is larger than the diameter of the second stepped surface 3112, and the first stepped surface 3111 is closer to the opening of the adapter cup 3 than the second stepped surface 3112.

[0027] The inner wall of the support buffer frame 4 is arranged correspondingly to the outer wall of the needle tube 11 and is interference-fitted. The outer wall of the support buffer frame 4 is arranged correspondingly to the inner wall of the adapter cup 3 and is inserted. The two ends of the support plate 43 along the axial direction of the cylinder 41 are flush with the cylinder 41 and extend along the radial outer direction of the cylinder 41 to form a support section. The inner side of the support section and the end face of the cylinder 41 form a clearance slot 45 that corresponds to the finger support end 111.

[0028] See Figure 5 The piston 12 is slidably disposed within the needle tube 11 and is sealed to the inner wall of the needle tube 11. The piston rod 13 is connected to the piston 12 and has a pre-cut end 131 near the piston 12. The tip 112 of the needle tube 11 is screwed with a Luer cap 2, and the other end is a finger support end 111. After the piston rod 13 breaks off at the pre-cut end 131, the needle tube 11 is inserted into the adapter cup 3 in either the first or second mounting position. After the piston rod 13 breaks off, a section connected to the piston 12 remains inside the needle tube 11, and the side of this section facing away from the piston 12 forms a cross-section.

[0029] Specifically, the catheter flushing device 1 includes two specifications: 10mL and 20mL. This embodiment takes the 20mL specification as an example. The component structures of the two specifications are the same, except that the inner diameter of the support buffer frame 4, the inner diameter of the adapter cup 3, and the diameter of each step surface 311 are adjusted according to the size of the corresponding needle tube 11 and Luer cap 2.

[0030] See Figure 8 The support buffer frame 4 includes a cylinder 41, a support plate 43, and a support ring 44. The inner wall surface of the cylinder 41 is provided with inner support ribs 42 extending along the axial direction of the cylinder 41. There are four inner support ribs 42, which are evenly arranged in an array along the circumference of the cylinder 41. Each inner support rib 42 extends along the axial direction of the cylinder 41 to both ends of the cylinder 41. The top surface of each inner support rib 42 is arranged correspondingly to the outer wall surface of the needle tube 11 and is interference-fitted. The diameter of the virtual envelope formed by the top surfaces of the four inner support ribs 42 is smaller than the outer diameter of the needle tube 11, and the difference between the two is 0.2mm to 0.6mm, preferably 0.4mm. That is, the single-sided interference along the radial direction is 0.1mm to 0.3mm, preferably 0.2mm. After the needle tube 11 is inserted into the cylinder 41, the tube wall is subjected to four radial holding forces distributed along the circumference. The stiffness of the support buffer frame 4 is transmitted to the tube wall of the needle tube 11 through the inner support ribs 42. The tube wall no longer relies solely on its own stiffness to resist the radial load in the centrifugal force field.

[0031] Specifically, the cross-section of the inner support rib 42 is rectangular, trapezoidal, or an arc shape with one side rounded off from the inner wall of the cylinder 41; the width of the inner support rib 42 is 2.5mm to 3.5mm, preferably 3.0mm; the height of the inner support rib 42 protruding from the inner wall of the cylinder 41 is 1.5mm to 2.5mm, preferably 2.0mm; the axial length of the inner support rib 42 is consistent with the axial length of the cylinder 41.

[0032] See Figure 8 The support plate 43 extends axially along the cylinder 41 and is fixedly connected to the outer wall of the cylinder 41. There are four support plates 43, which are evenly arranged in an array along the circumference of the cylinder 41. The support ring 44 is arranged circumferentially along the cylinder 41 and is fixedly connected to the support plate 43 to support each support plate 43. The outer edge of the support plate 43 is arranged and inserted into the inner wall of the adapter cup 3. The two ends of the support plate 43 along the axial direction of the cylinder 41 are flush with the cylinder 41. The outer part of the support plate 43 along the radial direction of the cylinder 41 extends axially to the end face of the cylinder 41, and the extended part forms a support section. The inner side of the support section and the end face of the cylinder 41 together form a relief groove 45. Thus, the support buffer frame 4 is centered in the adapter cup 3 with the outer edges of the four support plates 43, and the support section at one end of the corresponding annular support platform 31 bears the axial load.

[0033] See Figure 6 and Figure 7 The annular support platform 31 protrudes from the inner bottom surface of the adapter cup 3, and the stepped surface 311 is coaxially arranged with the adapter cup 3. The portion of the inner wall of the annular support platform 31 surrounding the first stepped surface 3111 corresponds to the outer periphery of the cross-section, and the portion surrounding the second stepped surface 3112 corresponds to the outer wall of the Luer cap 2. The upper platform of the annular support platform 31 and the first stepped surface 3111 are provided with weight-reducing structures to reduce the weight of the adapter cup 3 while ensuring the supporting strength.

[0034] See Figure 6 The outer wall of the adapter cup 3 is provided with reinforcing ribs 32. Multiple reinforcing ribs 32 are arranged along the circumference and axial direction of the adapter cup 3 and form a hollow gap with each other. While improving the bending and torsional resistance of the adapter cup 3, it reduces its weight and facilitates the transfer of load along the rib grid.

[0035] In one embodiment, the clearance slot 45 is used to avoid the finger support end 111. The outer edge of the finger support end 111 is spaced apart from the groove wall surface of the clearance slot 45 so that the support section of the support buffer frame 4 facing the annular support platform 31 directly abuts against the upper surface of the annular support platform 31.

[0036] In some embodiments, the inner wall surface of the cylinder 41 may not have the inner support rib 42, but instead a continuous cylindrical surface directly pressurized against the outer wall surface of the needle tube 11 to form a continuous circumferential covering and holding. In other embodiments, a clearance fit may be used between the inner wall surface of the cylinder 41 and the outer wall surface of the needle tube 11. In this case, the tube wall first undergoes a slight radial expansion during centrifugation, and then is restrained by contacting the top surface of the inner support rib 42 or the inner wall surface of the cylinder 41. The above two fitting methods can be used as implementation methods, and the specific scope of protection is subject to the claims; among them, the interference fit embodiment establishes the support of the tube wall before centrifugation begins, and the effect of suppressing deformation is more direct.

[0037] Specifically, the adapter cup 3 and the support buffer frame 4 can be made of at least one of the following: medical-grade polycarbonate, polysulfone, polyetheretherketone (PEEK), rigid polypropylene, glass fiber reinforced nylon, polyoxymethylene (POM), stainless steel, or aluminum alloy. For example, PEEK has a flexural strength of approximately 150 MPa, a compressive strength of approximately 200 MPa, and an elastic modulus of approximately 3.6 GPa; glass fiber reinforced nylon PA66 with GF30 has a flexural strength of approximately 180 MPa, a compressive strength of approximately 160 MPa, and an elastic modulus of approximately 8.0 GPa; medical-grade polypropylene has a flexural strength of approximately 50 MPa, a compressive strength of approximately 60 MPa, and an elastic modulus of approximately 1.5 GPa; and aluminum alloy 6061-T6 has a flexural and compressive strength of approximately 276 MPa and an elastic modulus of approximately 69 GPa. The final material selection should be determined by considering compatibility with cleaning agents, anticoagulants, and sterilization methods, dimensional stability, particle release, and manufacturing costs. The support buffer frame 4 is preferably made of transparent or semi-transparent materials such as polycarbonate or polysulfone, allowing observation of the blood layering interface and the height of each liquid column from the outside even when the syringe 11 is inside the support buffer frame 4. Phase sampling between centrifugation operations can be performed without removing the syringe 11 from the support buffer frame 4, avoiding disturbance of the established layering interface when disassembling the support buffer frame 4. When removing the support buffer frame 4 from the syringe 11, it is advisable to hold the support buffer frame 4 and slowly rotate it upwards along the axis of the syringe 11, gradually loosening the interference fit before removal. It is not advisable to forcefully pull it along the axis or pry it at an angle, as this may disturb the established layering interface. The adapter cup 3 and the support buffer frame 4 can be manufactured by injection molding or 3D printing; 3D printed parts are used in the prototype stage.

[0038] Specifically, based on a 20mL specification, a total blood mass of approximately 28.75g, an effective rotation radius of approximately 10cm, and a rotation speed of 1800RPM, the total centrifugal force is approximately 102.14N. When evenly distributed among the four inner support ribs 42, the load borne by each inner support rib 42 is approximately 25.53N, corresponding to a bending stress of approximately 25.53MPa and a shear stress of approximately 4.25MPa. The contact pressure between the inner support rib 42 and the wall of the needle tube 11 is approximately 0.30MPa. The above values ​​are engineering reference values ​​estimated under ideal load-sharing conditions; actual values ​​should be based on prototype testing and inspection data.

[0039] Example 1; See Figure 3 and Figure 4 In this embodiment, a first mounting position is adopted, where the finger support end 111 faces the annular support platform 31 and the tip 112 faces the opening of the adapter cup 3, which is suitable for the single-cycle centrifugation method for draining blood plasma. In this embodiment, the cross-section of the piston rod 13 after breaking off from the pre-break 131 abuts against the first step surface 3111, and the finger support end 111 falls into the clearance slot 45 at the end of the support buffer frame 4 facing the annular support platform 31. The support section of the support buffer frame 4 corresponding to the end of the annular support platform 31 abuts against the upper surface of the annular support platform 31.

[0040] The usage method of this embodiment is as follows: Slowly inject the collected anticoagulated whole blood into the syringe 11 of the catheter flushing device 1 to avoid generating too many air bubbles that may affect the subsequent centrifugation effect; the volume ratio of whole blood to anticoagulant is preferably 9:1, that is, 18 mL of whole blood is mixed with 2 mL of sodium citrate anticoagulant to form a nominal 20 mL input. This volume ratio can also be adjusted within the range of 7:1 to 12:1; then gently tighten the Luer cap 2 at the tip 112 of the syringe 11 to ensure that the interface is sealed and leak-free, preventing sample spillage or contamination during centrifugation. Hold the non-piston end of the piston rod 13, and smoothly break off the piston rod 13 along the pre-break 131 and discard the broken part, retaining only the main body of the syringe 11 with the piston 12, whole blood and Luer cap 2. The piston 12 remains inside the syringe 11 and maintains a sealed fit with the inner wall of the syringe 11.

[0041] Insert the finger support end 111 of the syringe 11 vertically downward and the tip 112 vertically upward into the adapter cup 3, so that the cross-section abuts against the first step surface 3111, and the finger support end 111 falls into the relief groove 45; then insert the support buffer frame 4 along the inner wall surface of the adapter cup 3, so that the top surface of the inner support rib 42 is interference-fitted with the outer wall surface of the syringe 11, and the support section of the support buffer frame 4 corresponding to one end of the annular support platform 31 abuts against the upper end of the annular support platform 31, thus completing the assembly.

[0042] Insert the adapter cup 3, containing the syringe 11, into the centrifuge cup, ensuring a tight fit between the outer wall of the adapter cup 3 and the inner wall of the centrifuge cup. After balancing, start the centrifuge at an exemplary speed of 1800 rpm for 10 minutes. After centrifugation, wait for the centrifuge to completely stop, remove the adapter cup 3 and pull out the syringe 11. At this point, the plasma layer is located on the side of the syringe 11 closest to the tip 112. The syringe 11, along with the support buffer 4, can be fixed to the support with the tip 112 facing upwards. Unscrew the Luer cap 2, connecting the tip 112 to an empty syringe via a three-way valve. Use a micro-pump or stroke motor to slowly aspirate the plasma layer through the three-way valve into the empty syringe. During the transfer, do not push the piston 12 inside the syringe 11 with the push rod. If further concentration is required, reload the transferred carrier into the adapter cup 3 and perform a second centrifugation at an exemplary speed of 2000 rpm for 10 minutes, then collect platelet-rich plasma.

[0043] Example 2; See Figure 1 and Figure 2 In this embodiment, a second mounting position is adopted, that is, the tip 112 faces the annular support platform 31 and the finger support end 111 faces the opening of the adapter cup 3, which is suitable for the double centrifugation method for removing red blood cells. In this embodiment, the Luer cap 2 is inserted along the inner wall surface surrounding the second step surface 3112 and abuts against the second step surface 3112. The finger support end 111 falls into the relief slot 45 at the end of the support buffer frame 4 facing away from the annular support platform 31. The support section of the support buffer frame 4 corresponding to one end of the annular support platform 31 abuts against the upper platform surface of the annular support platform 31.

[0044] The usage method of this embodiment is as follows: the steps of whole blood injection, sealing, and breaking the piston rod 13 are the same as in embodiment 1. Keep the Luer cap 2 vertically downward, slowly insert the tip 112 of the syringe 11 into the adapter cup 3 with the inner bottom surface facing it, so that the Luer cap 2 is precisely aligned with the second step surface 3112 and guided along the inner wall surface surrounding the second step surface 3112 until the end face of the Luer cap 2 is completely in contact with the second step surface 3112; then insert the support buffer frame 4 along the inner wall surface of the adapter cup 3, so that the top surface of the inner support rib 42 is in interference fit with the outer wall surface of the syringe 11, and the support section of the support buffer frame 4 corresponding to one end of the annular support platform 31 abuts against the upper platform surface of the annular support platform 31.

[0045] Insert the adapter cup 3 into the centrifuge cup, balance it, and start the centrifuge. Set the centrifugation parameters to 1500 rpm for 10 minutes to enter the first stage of centrifugation. During this process, the red blood cells in the blood, due to their higher density, will settle to the bottom of the syringe 11 near the Luer cap 2 under the action of centrifugal force. After centrifugation, wait for the centrifuge to stop completely, remove the adapter cup 3 and pull out the syringe 11; fix the syringe 11 together with the support buffer frame 4 with the Luer cap 2 facing down on the support, unscrew the Luer cap 2, and connect the tip 112 to an empty 20mL ordinary syringe through a three-way valve. There can be one three-way valve or two in series; drive the empty syringe with a micro-pump or stroke motor to slowly aspirate, transferring most of the red blood cell layer at the bottom of the syringe 11 to the empty syringe non-invasively through the three-way valve. The transfer device does not enter the stratified liquid column. The piston 12 in the syringe 11 slides with the liquid column as it moves down, without being pushed by the push rod. For example, stop aspirating when only about 0.5 mL of red blood cell fluid remains in syringe 11, close the three-way valve and screw the Luer cap 2 back on.

[0046] After removing most of the red blood cells, reinstall the syringe 11 into the adapter cup 3 as described above, ensuring that the connection between the syringe 11, the second step surface 3112, and the support buffer 4 is consistent with the initial assembly. Place the adapter cup 3 into the centrifuge cup again, start the centrifuge, set the parameters to 2000 rpm for 10 minutes, and perform the second stage of centrifugation. During this stage, platelets in the blood will further accumulate and settle to the bottom of the syringe 11, and the liquid column will show a plasma layer, a white membrane layer, and a residual red blood cell layer from top to bottom. After the second centrifugation, remove the adapter cup 3 and pull out the syringe 11. Keep the syringe 11 and the support buffer 4 together, with the Luer cap 2 facing down, and fix it on the support. Unscrew the Luer cap 2, connect an empty syringe through the three-way valve, and use the same aspiration method to sequentially aspirate the lower residual red blood cells and the platelet-rich plasma of the white membrane layer. Collect the platelet-rich plasma of the white membrane layer (exemplarily about 1 mL) into a dedicated syringe to complete the entire PRP separation and extraction process. The piston 12 is not pushed by the push rod during either transfer, so as to avoid disturbing the layered interface due to the difficulty in controlling the pushing stroke.

[0047] Specifically, the above centrifugation parameters can be adjusted according to the centrifuge model, effective rotation radius, and target product requirements. The relative centrifugal force should be recalculated from the actual effective rotation radius and verified against the value displayed on the equipment. After two centrifugations using the adapter assembly of this invention, the path of first removing red blood cells and then enriching the white blood cell layer can be selected according to the preparation target (Example 2), or the path of first taking plasma and then centrifuging and concentrating the plasma layer (Example 1), to obtain the corresponding type of PRP. Specific performance should be based on the examples, test data, and comparative experiments. Quality control may include platelet count, white blood cell count, residual red blood cell amount, and final product volume detection before and after centrifugation to establish a process calibration table.

[0048] Specifically, the catheter flushing device 1 is a sealed carrier, with its inner surface directly contacting the blood; the support buffer 4, the adapter cup 3, and the centrifuge cup are all located outside the syringe 11, only contacting the outer surface of the catheter flushing device 1 and not directly contacting the blood. The catheter flushing device 1, the support buffer 4, and the adapter cup 3 can be placed in independent barrier packaging to form a three-level packaging or sterile barrier configuration of inner, middle, and outer layers to meet the requirements of clinical aseptic operation.

[0049] Specifically, the phase extraction operation after centrifugation does not constitute a necessary technical feature of this utility model. In the above embodiments, phase extraction is performed by suction: after unscrewing the Luer cap 2 of the syringe 11, it is connected to the receiving syringe or receiving container via a three-way valve and connecting pipeline. The receiving syringe is driven by a micro-pump, a lead screw motor, or a manual distance pusher to aspirate. The selected phase is transferred to the receiving side without the transfer device entering the stratified liquid column or without the piston 12 being pushed by the push rod. The piston 12 inside the syringe 11 slides along with the liquid column. The above phase extraction method can be used in conjunction with the adapter assembly of this utility model, and this utility model is not limited to its specific form.

[0050] The specific principle and usage of the centrifuge adapter assembly for PRP preparation provided in this embodiment are as follows: After the needle 11 is inserted into the cylinder 41 of the support buffer frame 4, the inner wall surface of the cylinder 41 or the top surface of the inner support rib 42 on it forms an interference fit with the outer wall surface of the needle 11. The support buffer frame 4 applies a circumferentially distributed radial holding force to the tube wall along the tube body of the needle 11. After centrifugation begins, the blood in the tube exerts an outward radial load on the tube wall in the centrifugal force field. This load is no longer borne solely by the stiffness of the thin-walled tube body itself, but is transmitted to the support buffer frame 4 through the interference contact surface, and then to the adapter cup 3 through the insertion surface between the support plate 43 and the inner wall surface of the adapter cup 3, and finally borne by the centrifuge cup. The tube wall thus obtains the superposition of external stiffness, the degree of radial expansion and ellipticization is reduced, and the geometric boundary of blood stratification is maintained.

[0051] In the axial direction, each of the two mounting positions forms two parallel force transmission paths. In the first mounting position, the broken section of the piston rod 13 abuts against the first step surface 3111, forming the first path; the support section of the support buffer frame 4 corresponding to one end of the annular support platform 31 abuts against the upper surface of the annular support platform 31, directly transmitting the axial component force collected from the tube body through the clamping mechanism to the annular support platform 31, forming the second path. In the second mounting position, the Luer cap 2 abuts against the second step surface 3112, forming the first path; the support section of the support buffer frame 4 corresponding to one end of the annular support platform 31 abuts against the upper surface of the annular support platform 31, forming the second path. Because the two paths bear load in parallel, the contact stress at any point is lower than that under single-path load, and neither the sealing end nor the broken end is individually pressed, thus reducing the risk of the Luer cap 2 loosening and the piston 12 being passively displaced.

[0052] Since the first step surface 3111 and the second step surface 3112 are arranged sequentially along the axial direction of the same step surface 311, corresponding to the broken section of the piston rod 13 and the Luer cap 2 respectively, and since the clearance slots 45 are symmetrically opened at both ends of the support buffer frame 4, the finger support end 111 has space to settle in both orientations without being clamped. Therefore, the same support structure is used for both upright and inverted loading orientations. When switching the preparation mode, only the insertion orientation of the needle tube 11 needs to be changed, without replacing the adapter cup 3 or the support buffer frame 4.

[0053] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0054] The above description of the disclosed embodiments enables those skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A centrifugal adapter assembly for PRP preparation, for use with a catheter flushing device (1), the catheter flushing device (1) having a needle tube (11), finger supports (111) and a tip (112) located at both ends of the needle tube (11), a Luer cap (2) installed on the tip (112), a piston (12) disposed in the needle tube (11), and a piston rod (13) connected to the piston (12), the piston rod (13) being breakable from a pre-break (131), retaining a section connected to the piston (12) after breakage, the broken end of which is a cross-section, characterized in that, Includes an adapter cup (3) and a support cushion (4); The adapter cup (3) is used to be inserted into the centrifuge cup of the centrifuge. The inner bottom surface of the adapter cup (3) is provided with an annular support platform (31). The inner wall surface of the annular support platform (31) is formed with a stepped surface (311). The stepped surface (311) includes a first stepped surface (3111) and a second stepped surface (3112) arranged sequentially along the axial direction of the adapter cup (3). The support buffer frame (4) is detachably inserted into the adapter cup (3). The inner wall surface of the support buffer frame (4) is used for interference fit with the outer wall surface of the needle tube (11). The two ends of the support buffer frame (4) have relief slots (45) for accommodating the finger support end (111) on the side corresponding to the needle tube (11). The end face of the support buffer frame (4) corresponding to the annular support platform (31) abuts against the upper end surface of the annular support platform (31). The centrifugal adapter assembly has a first mounting position and a second mounting position for the catheter flusher (1) to be inserted into the adapter cup (3) either by the finger support end (111) or the tip (112); in the first mounting position, the first stepped surface (3111) is used to abut against the cross section, and the support buffer frame (4) has a relief slot (45) at one end of the annular support platform (31) to accommodate the finger support end (111); in the second mounting position, the second stepped surface (3112) is used to abut against the Luer cap (2).

2. The centrifuge adapter assembly for PRP preparation according to claim 1, characterized in that, The support buffer frame (4) includes a cylinder (41), a support plate (43), and a support ring (44). The inner wall of the cylinder (41) is provided with inner support ribs (42) extending axially along the cylinder (41). There are multiple inner support ribs (42), which are arranged at intervals along the circumference of the cylinder (41). The top surface of each inner support rib (42) is used for interference fit with the outer wall surface of the needle tube (11). The support plate (43) extends axially along the cylinder (41) and fits against the outer wall surface of the cylinder (41). The support ring (44) is fixedly connected to the support plate (43) along the circumference of the cylinder (41). The outer edge of the support plate (43) is arranged and inserted into the inner wall of the adapter cup (3). The two ends of the support plate (43) along the axial direction of the cylinder (41) are flush with the cylinder (41) and extend along the radial outer side of the cylinder (41) to form a support section. The support section abuts against the upper end of the annular support platform (31). The inner side of the support section forms the clearance groove (45) with the end face of the cylinder (41).

3. The centrifuge adapter assembly for PRP preparation according to claim 1, characterized in that, The groove wall of the relief slot (45) is arranged at a distance from the outer edge of the finger support end (111).

4. The centrifuge adapter assembly for PRP preparation according to claim 2, characterized in that, The number of the support plates (43) is four, and the four support plates (43) are arranged in a uniform array along the circumference of the cylinder (41).

5. The centrifuge adapter assembly for PRP preparation according to claim 2, characterized in that, The number of the inner support ribs (42) is four. The four inner support ribs (42) are arranged in a uniform array along the circumference of the cylinder (41), and each inner support rib (42) extends along the axial direction of the cylinder (41) to both ends of the cylinder (41).

6. The centrifuge adapter assembly for PRP preparation according to claim 2, characterized in that, The cross-section of the inner support rib (42) is rectangular, trapezoidal, or rounded on one side away from the inner wall of the cylinder (41).

7. The centrifuge adapter assembly for PRP preparation according to claim 2, characterized in that, The diameter of the virtual envelope formed by the top surfaces of the multiple inner support ribs (42) is smaller than the outer diameter of the needle tube (11), and the difference between the two is 0.2 mm to 0.6 mm.

8. The centrifuge adapter assembly for PRP preparation according to claim 1, characterized in that, The diameter of the first step surface (3111) is larger than the diameter of the second step surface (3112), and the first step surface (3111) is closer to the opening of the adapter cup (3) than the second step surface (3112); the portion of the inner wall of the annular support platform (31) surrounding the first step surface (3111) is arranged to correspond with the outer periphery of the cross section of the piston rod (13), and the portion surrounding the second step surface (3112) is arranged to correspond with the outer wall of the Luer cap (2).

9. The centrifuge adapter assembly for PRP preparation according to claim 1, characterized in that, The outer wall surface of the adapter cup (3) is provided with reinforcing ribs (32), and multiple reinforcing ribs (32) are arranged along the circumference and axial direction of the adapter cup (3) and form a hollow gap with each other.

10. The centrifuge adapter assembly for PRP preparation according to claim 1, characterized in that, The support buffer frame (4) is made of a transparent or semi-transparent material, which is polycarbonate or polysulfone.

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