Continuous administration device for small animals

Abstract

The invention relates to the technical field of small animal administration, and discloses a small animal continuous administration device which comprises a stainless steel capillary tube, the lower portion of the stainless steel capillary tube is bent, one end of the stainless steel capillary tube is used for being connected with a silicone tube in a small animal blood vessel, and the other end of the stainless steel capillary tube is exposed to be connected with an administration catheter. By defining the bending structure design of the stainless steel capillary tube, the device can be better attached to subcutaneous tissues of small animals, and interference to animal activities after implantation is reduced; due to vertical distribution and position limitation of the silica gel gasket and the non-woven disc, stable subcutaneous supporting of the device can be achieved, and displacement is avoided; a plurality of fiber growth holes are evenly distributed in the outer side of the non-woven disc, fibroblasts can be guided to grow in, the device and surrounding tissue are well integrated, the fixing stability is further improved, meanwhile, foreign matter reaction is reduced, the animal welfare requirement is met, the overall structure is simple, the size is miniaturized, and the requirement for long-term and repeatable drug delivery is met.

Description

Technical Field

[0001] This invention relates to the field of small animal drug delivery technology, specifically to a continuous drug delivery device for small animals. Background Technology

[0002] In scientific research in fields such as biomedicine, pharmacology, and toxicology, repeated and precise intravascular continuous drug delivery to small animals such as rats, mice, and rabbits is a core procedure in pharmacokinetic studies, toxicological evaluations, and long-term efficacy observations. To avoid the animal pain, risk of trauma and infection, and experimental data bias caused by traditional manual repeated punctures, various implantable small animal vascular drug delivery devices (i.e., "indwelling catheter systems" or "vascular access ports") have emerged on the market. Such existing devices are typically assembled from multiple precision components, including implantable catheters, subcutaneous implantation ports, and external connection devices, and have the following key drawbacks: The system has a complex structure and requires multiple components such as metal ports, connectors, and locking devices to achieve fixation and drug delivery. This not only increases the difficulty and time required for surgical implantation, but also increases the probability of postoperative complications such as catheter blockage and displacement. The device is large and bulky, with the subcutaneous implantation part being a protruding "box-shaped" structure that is not compatible with the size of small animals such as mice. After implantation, it will cause continuous pressure on the animal's skin and muscles, causing pain and tissue necrosis. At the same time, it restricts the animal's free movement and introduces stress factors that interfere with experimental results. The fixation method is not reliable enough. Existing devices mostly rely on single suture fixation or rigid base compression fixation, lacking a good integration design with surrounding tissues. The device is prone to displacement and overturning due to animal activity. In addition, the tension at the skin suture site is concentrated, making wound healing difficult and prone to secondary infection. The high manufacturing cost, complex multi-component structure, and use of special materials (such as medical titanium alloy and special silicone) make the device expensive and difficult to meet the needs of large-sample experiments or laboratories with limited budgets. Summary of the Invention

[0003] The purpose of this invention is to provide a continuous drug delivery device for small animals to solve the problems mentioned in the background art.

[0004] To achieve the above objectives, the present invention provides the following technical solution: a continuous drug delivery device for small animals, comprising: A stainless steel capillary tube, the lower part of which is bent, one end of which is used to connect to a silicone tube inside a small animal's blood vessel, and the other end is exposed to connect to a drug delivery catheter. A silicone pad and a non-woven disc are threaded through the outside of the stainless steel capillary tube, the non-woven disc being located above the silicone pad and above the bent part of the stainless steel capillary tube. A silicone nut is fitted on the upper part of the outer side of the stainless steel capillary tube, and the silicone nut is located above the nonwoven disc. A protective cap is fitted on the drug inlet end of the stainless steel capillary tube. Fiber growth holes are opened on the outer side of the nonwoven disc, and there are several fiber growth holes, which are evenly distributed along the circumference of the nonwoven disc.

[0005] As a further improvement of the present invention, the silicone pad is located at the bend of the stainless steel capillary, and the silicone nut is positioned below the nonwoven disc, maintaining the thickness of mouse skin.

[0006] As a further improvement of the present invention, the nonwoven disc has a thickness of 1 mm and a radius of 5 mm, and the fiber growth holes are divided into three equal parts located 3 mm from the center, with a radius of 1 mm.

[0007] As a further improvement of the present invention, the silicone nut has a radius of 2mm and a height of 6mm, and the inner diameter of the silicone nut is adapted to and tightly fitted with the outer diameter of the stainless steel capillary.

[0008] As a further improvement of the present invention, the contour of the subcutaneous adhesive portion of the stainless steel capillary is adapted to the curve of the small animal's body surface, and is in the form of a thin patch.

[0009] As a further improvement of the present invention, an anti-detachment component is provided between the protective cap and the stainless steel capillary tube. The anti-detachment component includes a pad, and the pad is fixedly sleeved at the drug inlet end of the stainless steel capillary tube. A protective cap is provided on the outside of the pad. A connecting mounting hole is opened on the outside of the stainless steel capillary tube and the pad. A stepped hole communicating with the mounting hole is opened on the outside of the protective cap. A push post located in the stepped hole is connected to one side of the inner cavity of the mounting hole by an elastic component. A connecting rod is movably sleeved in the inner cavity of the stepped hole. One end of the connecting rod is connected to a limiting post that contacts the push post.

[0010] As a further improvement of the present invention, the elastic component includes a telescopic rod and a spring, the two ends of the telescopic rod and the spring being connected to one side of the push post and one side of the mounting hole cavity, respectively, and the spring being sleeved on the outside of the telescopic rod.

[0011] As a further improvement of the present invention, the outer side of the push post is adapted to the curvature of the outer wall of the pad cylinder, and the shape of the side of the limiting post that contacts the push post is adapted to the outer side of the push post.

[0012] As a further improvement of the present invention, the stainless steel capillary has symmetrically distributed mounting holes, elastic components, push posts, connecting rods and limiting posts on both sides of the drug inlet end.

[0013] As a further improvement of the present invention, a positioning groove is provided on the outer side of the pad cylinder, and a positioning plate is installed on the inner wall of the protective cap, the positioning plate being located in the inner cavity of the positioning groove.

[0014] Compared with the prior art, the beneficial effects of the present invention are as follows: By clearly defining the bending structure design of the stainless steel capillary, the device can better fit the subcutaneous tissue of small animals, reducing interference with animal activities after implantation; the vertical distribution and positional limitation of the silicone pad and non-woven disc can achieve stable support of the device under the skin and prevent displacement; several fiber growth pores evenly distributed on the outer side of the non-woven disc can guide fibroblast ingrowth, enabling the device to integrate well with the surrounding tissue, further improving fixation stability, reducing foreign body reactions, meeting animal welfare requirements, and the overall structure is simple and miniaturized, taking into account the needs of long-term and reproducible drug delivery; By incorporating an anti-detachment component between the protective cap and the stainless steel capillary tube, and utilizing a combination of a pad, mounting hole, stepped hole, elastic component, push post, limiting post, and connecting rod, a reliable connection between the protective cap and the stainless steel capillary tube is achieved. This effectively prevents the protective cap from accidentally detaching during animal activity and avoids contamination or blood backflow caused by exposure of the capillary tube port. The structure allows for the installation and removal of the protective cap without additional tools, making it convenient to operate and not affecting drug delivery efficiency. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of the present invention 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 some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 This is a schematic diagram of the overall structure of a continuous drug delivery device for small animals according to the present invention; Figure 2 This invention relates to a continuous drug delivery device for small animals. Figure 1 Enlarged structural diagram at point A in the middle; Figure 3 This is a schematic diagram of the explosion structure of the anti-drop-off component of a continuous drug delivery device for small animals according to the present invention; Figure 4 This is a schematic diagram of the stepped orifice structure of a continuous drug delivery device for small animals according to the present invention; Figure 5 This is a cross-sectional view of the anti-drop-off component of a continuous drug delivery device for small animals according to the present invention; Figure 6 This invention relates to a continuous drug delivery device for small animals. Figure 5 Enlarged structural diagram at point B.

[0017] In the diagram: 1. Stainless steel capillary tube; 2. Silicone gasket; 3. Non-woven disc; 4. Silicone nut; 5. Protective cap; 6. Anti-fall component; 61. Gasket; 62. Mounting hole; 63. Stepped hole; 64. Telescopic rod; 65. Spring; 66. Push post; 67. Limiting post; 68. Connecting rod; 7. Fiber growth hole; 8. Positioning groove; 9. Positioning plate. Detailed Implementation

[0018] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] Please see Figures 1-6 The present invention provides a continuous drug delivery device for small animals, comprising: Stainless steel capillary 1, the lower part of stainless steel capillary 1 is bent, one end of stainless steel capillary 1 is used to connect to the silicone tube in the blood vessel of small animal, and the other end is exposed to connect to the drug delivery catheter. A silicone pad 2 and a non-woven disc 3 are inserted through the outside of stainless steel capillary 1. The non-woven disc 3 is located above the silicone pad 2. The silicone pad 2 and the non-woven disc 3 are located above the bent part of stainless steel capillary 1. A silicone nut 4 is fitted on the upper part of the outer side of the stainless steel capillary tube 1. The silicone nut 4 is located above the nonwoven disc 3. A protective cap 5 is fitted on the drug inlet end of the stainless steel capillary tube 1. Fiber growth holes 7 are opened on the outer side of the nonwoven disc 3. There are several fiber growth holes 7, and the several fiber growth holes 7 are evenly distributed along the circumference of the nonwoven disc 3.

[0020] By clearly defining the bending structure design of the stainless steel capillary 1, the device can better fit the subcutaneous tissue of small animals, reducing interference with animal activities after implantation; the vertical distribution and positional limitation of the silicone pad 2 and the non-woven disc 3 can achieve stable support of the device under the skin and avoid displacement; the several fiber growth pores 7 evenly distributed on the outer side of the non-woven disc 3 can guide fibroblasts to grow in, enabling the device to integrate well with the surrounding tissue, further improving fixation stability, reducing foreign body reactions, meeting animal welfare requirements, and the overall structure is simple and miniaturized, taking into account the needs of long-term and reproducible drug delivery.

[0021] In one embodiment of the present invention, the silicone pad 2 is located at the bend of the stainless steel capillary 1, and the silicone nut 4 is below the nonwoven disc 3, maintaining the thickness of mouse skin.

[0022] Positioning the silicone pad 2 at the bend of the stainless steel capillary tube 1 allows the bend structure to limit the silicone pad 2, preventing it from shifting during animal activity. The design that preserves the thickness of the mouse skin between the silicone nut 4 and the non-woven disc 3 adapts to the natural state of the skin tissue, avoids excessive pressure on the skin from the device, reduces the risk of skin necrosis and wound dehiscence, improves the animal's comfort after implantation, and promotes wound healing.

[0023] In one embodiment of the present invention, the nonwoven disc 3 has a thickness of 1 mm and a radius of 5 mm, and the fiber growth holes 7 are divided into three equal parts located 3 mm from the center, with a radius of 1 mm.

[0024] The dimensions of the nonwoven disc 3 (1mm thickness, 5mm radius) and the specific structure of the fiber growth pores 7 (three equal parts distributed at a distance of 3mm from the center, 1mm radius) are clearly defined. This ensures the structural strength of the nonwoven disc 3 and provides sufficient and uniform channels for fibroblast ingrowth, ensuring the uniformity and stability of the device's integration with subcutaneous tissue. The precise dimensional design allows the nonwoven disc 3 to be perfectly matched with the stainless steel capillary tube 1 and the silicone pad 2, taking into account both the miniaturization of the device and its structural reliability.

[0025] In one embodiment of the present invention, the silicone nut 4 has a radius of 2mm and a height of 6mm, and the inner diameter of the silicone nut 4 is adapted to and tightly fitted with the outer diameter of the stainless steel capillary tube 1.

[0026] The silicone nut 4, with a radius of 2mm and a height of 6mm, is designed to fit snugly with the outer diameter of the stainless steel capillary tube 1. This design securely fixes the stainless steel capillary tube 1 to the skin of the small animal, preventing the device from shifting or falling off due to the animal's movement. The snug fit also reduces the gap between the skin and the device, lowering the risk of pathogen invasion and reducing the probability of postoperative infection. Furthermore, the soft silicone material will not cause hard pressure damage to the skin.

[0027] In one embodiment of the present invention, the contour of the subcutaneous adhesive portion of the stainless steel capillary 1 is adapted to the curve of the small animal's body surface, and is in the form of a thin patch.

[0028] The thin, patch-like structure of the subcutaneous attachment portion of the stainless steel capillary 1, which conforms to the curve of the small animal's body surface, can minimize the abruptness of the device on the animal's body surface, reduce restrictions on the animal's normal behaviors such as activity, eating, and socialization, and avoid introducing stress factors that may interfere with experimental results. At the same time, the structure that fits the body surface can disperse the pressure of the device on local tissues, reduce the occurrence of pain, tissue necrosis, and chronic inflammation, and better meet the optimization requirements of the "3R principle".

[0029] In one embodiment of the present invention, an anti-detachment component 6 is provided between the protective cap 5 and the stainless steel capillary tube 1. The anti-detachment component 6 includes a pad 61. The pad 61 is fixedly sleeved at the drug inlet end of the stainless steel capillary tube 1. The protective cap 5 is provided on the outside of the pad 61. The stainless steel capillary tube 1 and the pad 61 are provided with a communicating mounting hole 62. The protective cap 5 is provided with a stepped hole 63 communicating with the mounting hole 62 on the outside. A push post 66 located in the stepped hole 63 is connected to one side of the inner cavity of the mounting hole 62 by an elastic component. A connecting rod 68 is movably sleeved in the inner cavity of the stepped hole 63. One end of the connecting rod 68 is connected to a limiting post 67 that contacts the push post 66.

[0030] By setting an anti-detachment component 6 between the protective cap 5 and the stainless steel capillary tube 1, and utilizing the cooperative structure of the pad 61, mounting hole 62, stepped hole 63, elastic component, push post 66, limiting post 67 and connecting rod 68, a reliable connection between the protective cap 5 and the stainless steel capillary tube 1 is achieved, effectively preventing the protective cap 5 from accidentally falling off during animal activity and preventing contamination or blood backflow caused by exposure of the capillary tube port. This structure allows for the installation and removal of the protective cap 5 without additional tools, making operation convenient and not affecting drug administration efficiency.

[0031] In one embodiment of the present invention, the elastic component includes a telescopic rod 64 and a spring 65. The two ends of the telescopic rod 64 and the spring 65 are respectively connected to one side of the push post 66 and one side of the inner cavity of the mounting hole 62. The spring 65 is sleeved on the outside of the telescopic rod 64.

[0032] The elastic component adopts a combination structure of telescopic rod 64 and spring 65, with spring 65 sleeved on the outside of telescopic rod 64. This provides a stable elastic driving force for push post 66, ensuring that push post 66 and limit post 67 always maintain reliable contact and guarantee the anti-drop effect. At the same time, the telescopic rod 64 restricts the deformation direction of spring 65, preventing spring 65 from shifting or twisting, improving the structural stability and service life of anti-drop component 6, and ensuring reliable protection in long-term implantation scenarios.

[0033] In one embodiment of the present invention, the outer side of the push post 66 is adapted to the curvature of the outer wall of the pad cylinder 61, and the shape of the side of the limiting post 67 that contacts the push post 66 is adapted to the outer side of the push post 66.

[0034] The outer side of the push post 66 is adapted to the curvature of the outer wall of the pad cylinder 61, and the shape of the side of the limiting post 67 that contacts the push post 66 is adapted to the outer side of the push post 66. This fitted structure design can increase the contact area between the push post 66 and the limiting post 67, making the force more uniform and avoiding component wear caused by local stress concentration. At the same time, the fitted structure can improve the accuracy of the cooperation between the two, ensure the limiting effect of the limiting post 67 on the push post 66, further enhance the anti-fall reliability of the protective cap 5, and avoid loosening or jamming.

[0035] In one embodiment of the present invention, the stainless steel capillary tube 1 has symmetrically distributed mounting holes 62, elastic components, push posts 66, connecting rods 68 and limiting posts 67 on both sides of the drug inlet end.

[0036] Symmetrically distributed mounting holes 62, elastic components, push posts 66, connecting rods 68, and limiting posts 67 are provided on both sides of the drug inlet end of the stainless steel capillary tube 1. This ensures that the fixing force on the protective cap 5 is symmetrical and uniform, avoiding tilting or poor sealing of the protective cap 5 due to unilateral force. The symmetrical structure also improves the balance performance of the device, reduces component damage caused by unilateral force during animal activity, extends the service life of the device, and facilitates processing and assembly, reducing production difficulty.

[0037] In one embodiment of the present invention, a positioning groove 8 is provided on the outer side of the pad 61, and a positioning plate 9 is installed on the inner wall of the protective cap 5. The positioning plate 9 is located in the inner cavity of the positioning groove 8.

[0038] By opening a positioning groove 8 on the outside of the pad 61 and installing a positioning plate 9 on the inner wall of the protective cap 5, with the positioning plate 9 located in the inner cavity of the positioning groove 8, the protective cap 5 and the pad 61 can be precisely positioned and installed, avoiding misalignment of the protective cap 5 during installation, ensuring the coaxiality of the protective cap 5 and the stainless steel capillary tube 1, and improving the sealing effect; at the same time, the positioning structure can restrict the circumferential rotation of the protective cap 5, preventing the components of the anti-drop component 6 from being misaligned due to rotation, and ensuring the stable implementation of the anti-drop function.

[0039] Working principle: The lower part of the stainless steel capillary tube 1 is designed to be bent, so that its subcutaneous attachment part can be precisely adapted to the curve of the small animal's body surface, forming a thin patch that fits tightly against the subcutaneous tissue, reducing interference with the animal's activities; the silicone pad 2 is positioned at the bent part of the stainless steel capillary tube 1, and the bending structure forms a limit to prevent the silicone pad 2 from shifting. At the same time, the silicone pad 2 and the non-woven disc 3 above form a double-layer support structure, providing a stable subcutaneous support foundation for the device; The fiber growth pores 7 evenly distributed on the outer side of the nonwoven disc 3 provide channels for fibroblast ingrowth. After implantation, fibroblasts gradually grow into the pores, enabling the nonwoven disc 3 to integrate well with the surrounding tissue, forming a biological fixation and preventing the device from shifting, flipping, or falling off. The silicone nut 4 at the top fits tightly with the outer diameter of the stainless steel capillary 1, and the thickness of mouse skin is maintained between the bottom and the nonwoven disc 3. This not only firmly fixes the device to the skin but also avoids compressing the skin, further enhancing the fixation stability and reducing the risk of pathogen invasion. When no medication is being administered, the protective cap 5 is reliably connected to the stainless steel capillary tube 1 via the anti-drop component 6. The positioning groove 8 on the outer side of the pad 61 cooperates with the positioning plate 9 on the inner wall of the protective cap 5 to ensure that the protective cap 5 and the stainless steel capillary tube 1 are positioned coaxially and achieve a seal. In the anti-drop component 6, the elastic component drives the push post 66 to fit tightly with the limiting post 67 through the telescopic rod 64 and the spring 65. The structural design of the push post 66 being adapted to the curvature of the outer wall of the pad 61 and the limiting post 67 fitting with the push post 66 makes the protective cap 5 securely locked, effectively isolating air and preventing blood backflow and port contamination. During drug administration, pressing the connecting rod 68 causes the limiting post 67 to disengage from the push post 66, releasing the anti-drop lock, and the protective cap 5 can be removed. One end of the stainless steel capillary tube 1 is connected to the silicone tube inside the blood vessel of the small animal, and the other end is exposed as a drug administration interface. After connecting the external drug administration catheter to the exposed end, the drug is accurately delivered into the blood vessel through the channel of the stainless steel capillary tube 1 to achieve continuous drug administration. After drug administration, the protective cap 5 is put back on, the positioning plate 9 is embedded in the positioning groove 8 to complete the positioning, and the elastic component drives the push post 66 to reset and fit with the limiting post 67, achieving locking and sealing again, ensuring the reliability of the device for long-term use.

[0040] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A continuous drug delivery device for small animals, characterized in that, include: A stainless steel capillary tube (1) is bent at the bottom. One end of the stainless steel capillary tube (1) is used to connect to a silicone tube inside the blood vessels of a small animal, and the other end is exposed to connect to a drug delivery catheter. A silicone pad (2) and a non-woven disc (3) are inserted through the outside of the stainless steel capillary tube (1). The non-woven disc (3) is located above the silicone pad (2). The silicone pad (2) and the non-woven disc (3) are located above the bent part of the stainless steel capillary tube (1). A silicone nut (4) is fitted on the upper part of the outer side of the stainless steel capillary (1). The silicone nut (4) is located above the nonwoven disc (3). A protective cap (5) is fitted on the drug inlet end of the stainless steel capillary (1). Fiber growth holes (7) are opened on the outer side of the nonwoven disc (3). There are several fiber growth holes (7), and the several fiber growth holes (7) are evenly distributed along the circumference of the nonwoven disc (3).

2. The continuous drug delivery device for small animals according to claim 1, characterized in that, The silicone pad (2) is located at the bend of the stainless steel capillary (1), and the silicone nut (4) is positioned below the nonwoven disc (3) to retain the thickness of mouse skin.

3. The continuous drug delivery device for small animals according to claim 1, characterized in that, The nonwoven disc (3) has a thickness of 1 mm and a radius of 5 mm. The fiber growth holes (7) are divided into three equal parts located 3 mm from the center, and the radius of the fiber growth holes (7) is 1 mm.

4. A continuous drug delivery device for small animals according to claim 1, characterized in that, The silicone nut (4) has a radius of 2mm and a height of 6mm. The inner diameter of the silicone nut (4) is adapted to and tightly fitted with the outer diameter of the stainless steel capillary tube (1).

5. A continuous drug delivery device for small animals according to claim 1, characterized in that, The contour of the subcutaneous adhesive portion of the stainless steel capillary (1) is adapted to the curve of the small animal's body surface, and is in the form of a thin patch.

6. A continuous drug delivery device for small animals according to claim 1, characterized in that, An anti-drop component (6) is provided between the protective cap (5) and the stainless steel capillary tube (1). The anti-drop component (6) includes a pad (61). The pad (61) is fixedly sleeved at the drug inlet end of the stainless steel capillary tube (1). The protective cap (5) is provided on the outside of the pad (61). A connecting mounting hole (62) is opened on the outside of the stainless steel capillary tube (1) and the pad (61). A stepped hole (63) communicating with the mounting hole (62) is opened on the outside of the protective cap (5). A pusher (66) located in the stepped hole (63) is connected to one side of the inner cavity of the mounting hole (62) by an elastic component. A connecting rod (68) is movably sleeved in the inner cavity of the stepped hole (63). One end of the connecting rod (68) is connected to a limiting post (67) that contacts the pusher (66).

7. A continuous drug delivery device for small animals according to claim 6, characterized in that, The elastic component includes a telescopic rod (64) and a spring (65). The two ends of the telescopic rod (64) and the spring (65) are respectively connected to one side of the push post (66) and one side of the inner cavity of the mounting hole (62). The spring (65) is sleeved on the outside of the telescopic rod (64).

8. A continuous drug delivery device for small animals according to claim 6, characterized in that, The outer side of the push post (66) is adapted to the curvature of the outer wall of the pad (61), and the shape of the side of the limiting post (67) that contacts the push post (66) is adapted to the outer side of the push post (66).

9. A continuous drug delivery device for small animals according to claim 6, characterized in that, The stainless steel capillary (1) has symmetrically distributed mounting holes (62), elastic components, push posts (66), connecting rods (68) and limiting posts (67) on both sides of the drug inlet end.

10. A continuous drug delivery device for small animals according to claim 6, characterized in that, The outer side of the pad (61) is provided with a positioning groove (8), and the inner wall of the protective cap (5) is provided with a positioning plate (9), which is located in the inner cavity of the positioning groove (8).

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