A biomimetic scavenger fish multi-scale suction disc for non-destructive adsorption fixation of organ tissues

Abstract

The application discloses a multi-scale sucker of a biomimetic scavenger fish for non-destructive adsorption fixation of organ tissues. The sucker comprises a lip disc with a stiffness gradient characteristic, a pre-valve cavity and a post-valve cavity, the lip disc is provided with a biomimetic papilla structure and a mucus secretion flow channel, and a side wall of the sucker is provided with a negative pressure through hole. Through the multi-scale biomimetic mechanism of coupling negative pressure adsorption, chemical adhesion and capillary force adsorption, the sucker can realize high-strength, high-reliability and non-destructive adsorption fixation on the surface of wet and soft organ tissues, can be used for traction and stabilization of tissues in minimally invasive surgery, and can effectively expand and maintain the exposure of an operation field.

Description

Technical Field

[0001] This invention relates to the field of biomimetic suction cup technology, specifically to a biomimetic scavenger fish multi-scale suction cup for non-destructive adsorption and fixation of organs and tissues. Background Technology

[0002] In minimally invasive surgery (MIS), especially laparoscopic and robot-assisted surgery, safely and effectively manipulating, tractioning, fixing, and exposing delicate internal organs (such as the liver, intestines, and kidneys) is a crucial and challenging aspect. Ideal manipulators should provide sufficient suction to maintain surgical field exposure while minimizing mechanical damage to tissues, such as compression, tearing, and ischemia.

[0003] Currently, the main clinical techniques for tissue traction and fixation include mechanical clamping instruments and single negative pressure suction cup instruments. However, these are difficult to form and maintain an effective seal for organs and tissues that are often covered with body fluids or blood and have irregular surface morphology. Rigid clamping points or high negative pressure can easily cause adsorption damage, leading to excessive stretching, congestion, or even ischemia of local tissues. Most existing medical suction cups only provide simple adsorption and traction functions and lack more refined operation capabilities or adaptive attachment capabilities on complex curved surfaces.

[0004] In recent years, bionics has provided new ideas for solving the above problems. In nature, the pleco has attracted much attention from researchers due to its unique adsorption ability. Its sucker is an ingenious multi-scale structure, mainly composed of two parts: on the macroscopic scale, the pleco's lip disc, anterior valve cavity, and posterior valve cavity form a chamber that can generate negative pressure; on the microscopic scale, the mucous glands on the lip disc secrete chemical mucus, and the papillae of the lip disc seal with the mucus and water layer to generate capillary force, which helps to enhance adsorption.

[0005] Inspired by this, a biomimetic suction cup with a multi-scale adsorption mechanism similar to that of pleco fish was designed. This novel structure exhibits excellent adsorption performance, variable stiffness, and integrates multiple adsorption mechanisms to meet diverse needs. The suction cup achieves high-strength, high-reliability sealing adsorption on moist, soft organ tissue surfaces; it maximizes tissue protection throughout the adsorption process, enabling non-destructive procedures; and it can be integrated into other surgical devices, flexibly adjusted according to requirements, improving surgical efficiency and safety. Summary of the Invention

[0006] The purpose of this invention is to overcome the problems of existing medical devices, such as easy damage to organs and tissues, poor adsorption and sealing, and limited functionality, and to provide a biomimetic pleco multi-scale suction cup for non-destructive adsorption and fixation of organs and tissues. This suction cup mimics the multi-scale structure and mechanism of the pleco's adsorbent, enabling high-strength, high-reliability, and non-destructive adsorption operation on moist and soft organ and tissue surfaces.

[0007] To achieve the above objectives, the present invention adopts the following technical solution: a biomimetic scavenger fish multi-scale suction cup for non-destructive adsorption and fixation of organ tissues, specifically comprising the following: a lip disc, an anterior valve cavity, and a posterior valve cavity connected in sequence. The lip disc, anterior valve cavity, and posterior valve cavity are made of materials with increasing hardness, forming a stiffness gradient structure. The outer surface of the lip disc is provided with biomimetic papillary microstructures, which are distributed in a specific pattern along the longitudinal direction of the lip disc; the sidewall of the suction cup is provided with lateral through holes for connecting a negative pressure device; the suction cup is embedded with a flow channel system for secreting simulated mucus onto the outer surface of the lip disc.

[0008] This invention achieves adsorption through a multi-scale coupling mechanism: First, gas is drawn in through the lateral through-holes, creating negative pressure within the suction cup cavity and generating the primary adsorption force; second, mucus is secreted through the flow channel system, utilizing its chemical adhesion to enhance sealing and adsorption; finally, the biomimetic papillary microstructures on the lip disc surface interact with the mucus in a slippery environment, generating capillary adsorption force, further strengthening the adsorption effect. The soft lip disc ensures close contact with irregular tissue surfaces, while the rigid post-valve cavity effectively resists deformation and maintains cavity stability when negative pressure is generated.

[0009] The technical effects and advantages of this invention are as follows: 1. Excellent adsorption performance: It comprehensively utilizes three mechanisms—negative pressure adsorption, chemical adhesion, and capillary adsorption—significantly improving the adsorption strength and reliability on the surface of moist biological tissues; 2. Non-destructive operation: The stiffness gradient structure and soft lip design avoid the crushing injury caused by traditional mechanical clamps, while also avoiding tissue stretching damage caused by single high negative pressure, achieving maximum protection of organ tissues; 3. Strong surface adaptability: The biomimetic umbrella-shaped opening structure and flexible materials enable the suction cup to adapt well to various complex and irregular organ tissue surfaces; 4. Functional integration: It integrates adsorption, traction, and optional mucus secretion functions, improving the operational efficiency and safety in minimally invasive surgery. Attached Figure Description

[0010] Figure 1 A biomimetic multi-scale soft suction cup model;

[0011] Figure 2 Side view of the mold on the biomimetic multi-scale soft suction cup;

[0012] Figure 3For the central mold of biomimetic multi-scale soft suction cups;

[0013] Figure 4 A mold for a biomimetic multi-scale soft suction cup;

[0014] Figure 5 A mold for a biomimetic multi-scale soft suction cup groove;

[0015] Figure 6 Assembly drawing for a biomimetic multi-scale soft suction cup mold;

[0016] Figure 7 A schematic diagram of a biomimetic multi-scale soft suction cup with a stiffness gradient material.

[0017] Figure 21: Postvalvular space; 2: Anterior valve space; 3: Lip disc Detailed Implementation

[0018] To make the technical means, creative features, objectives and effects of the present invention easier to understand, the present invention will be further described below with reference to specific illustrations. In the description of the present invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation", "connection" and "connection" should be interpreted broadly. For example, they can be fixed connections, detachable connections, integral connections, mechanical connections, or electrical connections; they can be direct connections or indirect connections through an intermediate medium; and they can be internal connections between two components.

[0019] Example

[0020] like Figure 1 As shown, a biomimetic pleco multi-scale sucker for non-destructive adsorption and fixation of organs and tissues is presented. This design, based on biomimetic principles, integrates mechanical design methods and materials science knowledge. First, the adsorption mechanism of the pleco is analyzed. The sucker primarily relies on the vacuum negative pressure generated by the internal cavity as the main adsorption force, while the capillary force generated by the papillary structure on the lip disc and the chemical adhesion effect of its secreted mucus assist in adsorption and desorption. Next, the components of the sucker are studied, revealing that it consists of a lip disc, an anterior valve cavity, and a posterior valve cavity. Further material and structural analysis shows that the lip disc has the lowest stiffness, followed by the anterior valve cavity, and the posterior valve cavity has the highest stiffness, thus forming a layered structure with a stiffness gradient; simultaneously, its structure exhibits lateral distribution characteristics. Finally, the pleco-inspired soft sucker was successfully fabricated through the design of internal and external molds and a mold forming method.

[0021] Specifically, it includes the following:

[0022] (1) Adsorption mechanism analysis: The adsorption principle is based on the negative pressure formed by the water flow inside the suction cup cavity; the adsorption principle is based on the chemical adhesion of the mucus secreted by the mucous glands of the labial disc; and the adsorption principle is based on the capillary force formed by the closed layer of secreted mucus and water layer of the labial disc papillae.

[0023] (2) Analysis of sucker components: The sucker of the pleco is mainly composed of the lip disc, the anterior valve cavity and the posterior valve cavity. The adsorption site is mainly composed of the lip disc and the anterior valve cavity. The papillary structure on the lip disc can enhance the adsorption effect, and the posterior valve cavity plays a role in stabilizing the adsorption position of the sucker. Through scanning electron microscopy, it was observed that mucous glands are distributed on the lip disc, and the secreted chemical mucus plays a role in enhancing adsorption.

[0024] (3) Analysis of sucker structure characteristics: Fish dissection shows that the suckers of the pleco exhibit a lateral distribution in terms of structural characteristics; live observation video shows that before the pleco attaches to the glass wall, the lip disc is pulled open into an umbrella shape by the muscles to better adapt to the adsorption surface; the pleco sucker generates negative pressure laterally, making its adsorption more reliable and adaptable. Therefore, a lateral vacuum extraction hole is reserved near the gill opening of the sucker; the papilla structure is mostly hemispherical and arranged from small to large and then back to small in the longitudinal direction of the lip disc. In order to simulate the capillary adsorption of the papilla, a hemispherical structure arranged from small to large and then back to small in the longitudinal direction needs to be designed on the lip disc to imitate the structure of the papilla; several small pores for secreting mucus are observed on the lip disc through scanning electron microscopy.

[0025] (4) Analysis of sucker material characteristics: CT scan imaging of the sucker of the pleco was performed, and the CT scan imaging showed that the sucker of the pleco exhibited a stiffness gradient in material characteristics; the tissue of the lip disc and the anterior cavity of the valve was relatively soft, while the posterior cavity of the valve was relatively hard; the lip disc, as the direct contact part of the adsorption surface, has a softer material that can better adapt to various complex adsorption surfaces, and the papillary structure on it can enhance the adsorption performance of the sucker through capillary action in a slippery environment; the hard posterior cavity of the valve can maintain a small deformation when negative pressure is formed by the internal water flow, which helps to generate negative pressure; the mucous glands secrete chemical mucus, which enhances the adsorption effect;

[0026] (5) Preparation of the sucker: Using a 30cm long pleco as the research object, a plaster casting experiment was conducted on the internal cavity of the pleco to obtain a complete plaster model of the internal cavity. The plaster model was then 3D scanned to obtain a corresponding three-dimensional digital model. A biomimetic pleco sucker model was designed using Solidworks software, resulting in a basic biomimetic sucker model. By filming a video of the live suction process, the shape of the lip of the basic sucker model was modified to mimic the umbrella-like shape of the pleco's lips, such as... Figure 1 As shown. A mold is then manufactured using the model, and this model includes an upper mold, a center mold, a lower mold, and a groove mold, as shown. Figure 2 , Figure 3 , Figure 4 and Figure 5 As shown, after assembly... Figure 6As shown. Among them, the lip disc tissue of the suction cup is the softest, using Ecoflex 00-50; the anterior valve cavity is relatively soft, using Dragon Skin 30; and the posterior valve cavity is the hardest, using Smooth-Sil 960. First, prepare the lip plate using a mold: Take equal volumes or weights of type A and type B silicone solutions, following the principle of pouring type B silicone solution first, then type A. After pouring in the type A silicone solution, thoroughly mix the silicone mixture in the same direction with a stirring rod. While stirring, scrape the bottom and outside of the beaker with the stirring rod to prevent sedimentation on the beaker walls and bottom. Then, use a vacuum pump to remove air bubbles for 3 to 5 minutes. When the silicone solution poured in the first pour no longer flows significantly, pour the anterior valve cavity in the same way, cover it with the groove mold, leaving space for a flexible tube to simulate a mucous gland. Let it stand and cure for 16 hours before demolding. Then, pre-embed a thin flexible tube of appropriate length, connected end to end, in the groove to prevent blockage when pouring subsequent silicone solutions. After that, pour the hardest posterior valve cavity (silicone ratio of 10:1), let it stand and cure for 16 hours before demolding. Finally, micropores are created in the lip disc region, extending through the soft tube, to form a mucus secretion channel, resulting in a laterally adsorbed soft sucker with a stiffness gradient, mimicking the soft body of a pleco.

[0027] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A biomimetic multi-scale sucker from a scavenger fish for non-destructive adsorption and fixation of organs and tissues, characterized in that, Specifically, it includes the following: (1) The lip disc, anterior valve cavity and posterior valve cavity are connected in sequence, and the material hardness of the lip disc, anterior valve cavity and posterior valve cavity increases in sequence to form a variable stiffness gradient structure. (2) The outer surface of the lip disc is provided with multiple hemispherical protrusions for simulating the structure of the papilla; (3) The suction cup sidewall is provided with a lateral through hole for connecting the negative pressure device; (4) The suction cup is equipped with a flow channel system for simulating mucus secretion.

2. The biomimetic multi-scale suction cup according to claim 1, characterized in that, The multiple hemispherical protrusions on the lip disc are arranged in a pattern of increasing size and then decreasing in size along their longitudinal direction.

3. The biomimetic multi-scale suction cup according to claim 1, characterized in that, The flow channel system includes a flexible tube pre-embedded in the anterior cavity of the valve, and micropores penetrating the lip disc and communicating with the flexible tube.

4. A method for preparing a biomimetic scavenger fish multi-scale sucker for non-destructive adsorption and fixation of organs and tissues, characterized in that, Includes the following steps: S1. Based on the umbrella-shaped shape formed by the opening of the lip disc when the pleco is about to attach, a three-dimensional model is created to produce a mold with a lip disc cavity, an anterior valve cavity, and a posterior valve cavity. A groove structure for placing a flexible tube is set in the anterior valve cavity. S2. A lip plate is formed by casting a first flexible material; S3. The anterior valve cavity is formed by casting a second flexible material. After casting, the groove mold is immediately covered to form a groove structure for placing the tubing. After the material solidifies, the tubing is pre-embedded in the groove. S4. A third flexible material is used to cast and form the posterior cavity of the valve, wherein the hardness of the first flexible material is less than that of the second flexible material, and the hardness of the second flexible material is less than that of the third flexible material. S5. After demolding, micropores are made in the lip plate area to penetrate the hose, forming a mucus secretion channel.

5. The biomimetic multi-scale suction cup according to claim 4, characterized in that, The first flexible material is Ecoflex00-50, the second flexible material is Dragon Skin 30, and the third flexible material is Smooth-Sil960.

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