Anti-adhesion and drag-reducing urinary catheter with a bionic fixator

Abstract

The present application relates to the field of medical catheters, and specifically discloses an anti-adhesive drag-reducing urinary catheter with a bionic fixator. The bionic fixator is tightly attached to the middle section of the urethra by means of a bulging uneven surface combined with a micron-scale adhesive protrusion structure on the outer wall that mimics a frog's foot, so that some patients can exert the urination control function of the bladder and the internal urethral sphincter, reduce the operation of inserting the bladder and the stimulation of foreign objects on the bladder, and fully drain urine from a low position; when the fixator is in contact with the urethra and fixed, it effectively prevents the urinary catheter from slipping out, reduces urine leakage due to the mismatch of thin urinary catheters, and reduces the friction damage and infection risk to the urethra caused by frequent replacement of thick urinary catheters; at the same time, a bionic anti-adhesive drag-reducing structure is provided on the inner wall of the urinary flow channel of the bionic catheter to reduce the adhesion of the inner wall to urine, stones, blood and bacteria, thereby reducing the adhesion scaling, stone deposition and blockage infection caused by the long-term immersion of the inner catheter in urine, and increasing the safety and convenience of long-term indwelling catheterization.

Description

Technical Field

[0001] The present application relates to the field of medical catheters, and in particular to an anti-adhesion and drag-reducing urinary catheter with a bionic fixator. Background Art

[0002] For problems such as urinary difficulties caused by physiological and disease factors, indwelling urinary catheters are still the main means of alleviating urinary disorders, and their clinical application is becoming more and more widespread. However, this operation is invasive. During the insertion, removal and retention of thick catheters, large areas of friction are generated on the bladder and urethra, which can easily damage the patient's mucosa and cause bladder or urethral infection. On the other hand, the length of the catheter that penetrates deep into the bladder is too large, and the catheter opening is easily blocked by crystals due to long-term immersion in urine. At the same time, patients who use bladder-fixated catheters for a long time are at high risk of bladder atrophy. In order to prevent urine leakage, they need to use thicker catheters, which seriously affects the patient's experience.

[0003] Currently, some catheters with super-lubricating, hydrophilic coatings are available on the market. These coatings, upon contact with water, form a lubricating film between the catheter surface and the delicate urethral tissue, reducing friction and irritation from the catheter's outer wall, alleviating the risk of damage and infection. However, long-term indwelling catheters still present the problem of deep insertion into the bladder and friction with the urethra. This can significantly impair the patient's urination control system, making urinary reflux into the bladder highly susceptible to infection. Furthermore, the increasing thickness of the catheter increases the risk of urethral damage and infection. Summary of the Invention

[0004] In order to improve the safety and convenience of long-term indwelling urinary catheterization, the present application provides an anti-adhesion and drag-reducing urinary catheter with a bionic fixator.

[0005] The present application provides an anti-adhesive and drag-reducing urinary catheter with a bionic fixator, which adopts the following technical solutions:

[0006] An anti-adhesion and drag-reducing urinary catheter with a bionic fixator comprises a urinary catheter body and a bionic fixator arranged on the urinary catheter body;

[0007] The catheter body includes a main catheterization channel and an air / liquid channel; the inner wall of the main catheterization channel is provided with a bionic anti-viscosity and drag reduction structure for reducing the viscosity and friction of urine on the inner wall of the main catheterization channel;

[0008] The bionic fixator includes an elastic tube and a micron-scale adhesive protrusion structure;

[0009] The elastic tube is located at the head and neck of the catheter body, the cavity between the elastic tube and the catheter body is connected to the inflation / liquid channel, and is sealed at the air / liquid inlet of the inflation / liquid channel;

[0010] The micron-scale adhesion protrusion structure includes a plurality of micron-scale adhesion protrusion units arranged in an array on the outer wall of the elastic tube;

[0011] When the elastic tube bulges and deforms, the micron-scale adhesion protrusion structure on the outer wall is supported, so that the bionic fixator is in contact and adhesion with the urethra.

[0012] The bionic fixator provided in this application is fixed to the urethra, allowing some patients to continue to use the bladder and internal urethral sphincter to control urination, reducing the risk of bladder atrophy. Because it avoids the need for insertion into the bladder and has a short insertion length, it reduces foreign body irritation to the bladder and helps prevent urinary reflux infections. Furthermore, by fully draining urine from a position below the bladder, it reduces the chance of clogging the catheter port due to long-term immersion in bladder urine, thereby improving the safety and convenience of long-term indwelling catheterization.

[0013] The uneven deformation of the bulging surface of the bionic holdfast, combined with the micron-scale adhesive protrusion structure on the outer wall of the elastic tube that imitates the feet of a frog, achieves double fixation, prevents the bionic holdfast from slipping, and reduces urine leakage due to the mismatch of thin catheters; the fixation of the catheter in the urethra does not depend on the diameter of the catheter body, which helps to avoid damage to the urethra and the risk of infection caused by frequent replacement of thick catheters.

[0014] Furthermore, the elastic tube is a banded ring tube or an inner hole tube, wherein:

[0015] The banded ring tube is a smooth ring tube with a band arranged inside the wall. The band is elastic and has smaller elastic deformation than the smooth ring tube. The cavity between the inner wall of the banded ring tube and the outer wall of the urinary catheter body is a closed chamber connected to the inflation / liquid channel.

[0016] A bundle-shaped hole is provided inside the wall surface of the inner bore pipe, and the bundle-shaped hole is communicated with the air / liquid channel.

[0017] Furthermore, the unfolded structure of the bundle includes any one of vertical lines, spirals, rings, diagonal lines, and mesh lines, or a combination of several of them.

[0018] Furthermore, the bundled channels include channels of any one of vertical, spiral, annular, diagonal, and reticular shapes, or a combination of several of these shapes that are interconnected.

[0019] Furthermore, after the bionic fixator is filled with gas or liquid, the presence of the bundle-shaped belt or the bundle-shaped channel causes the elastic tube to deform with an uneven surface.

[0020] Furthermore, the micron-scale adhesion protrusion unit is a polygonal prism, and the height of the micron-scale adhesion protrusion unit is 0.1-2.0 times the diameter of the circumscribed circle of the bottom surface of the polygonal prism.

[0021] Furthermore, the center distance between adjacent micron-sized adhesion protrusion units is 1.0-2.0 times the diameter of the circumscribed circle of the bottom surface of the polygonal prism.

[0022] The bionic holdfast uses the micron-scale adhesive protrusion structure on its surface that mimics the frog's feet to achieve fixation. The principle is as follows: the microchannels formed between the micron-scale adhesive protrusion units can accommodate liquid. On the one hand, the microchannels help the liquid diffuse to the entire surface of the bionic holdfast, so as to discharge the gas between the surface of the bionic holdfast and the urethra wall that causes the adhesion to decrease; on the other hand, under humid conditions, the microchannels help to discharge excess liquid between the surface of the bionic holdfast and the urethra wall, thereby effectively increasing solid-solid contact and improving adhesion.

[0023] The micron-scale adhesion protrusion units are set to appropriate sizes and spacings to create negative pressure between the bionic fixator and the urethra wall, restricting liquid circulation to enhance the adhesion effect.

[0024] The micron-sized adhesive protrusions can also enhance adhesion by setting an appropriate protrusion height. Because the gaps between the micron-sized adhesive protrusions are very small, if the protrusion height is too high, the micron-sized adhesive protrusions tend to bend and aggregate, reducing the effective contact area between the micron-sized adhesive protrusions and the urethra wall, resulting in a decrease in adhesion. If the protrusion height is too low, the depth of the microchannels between the micron-sized adhesive protrusions is too small, affecting the wet adhesion effect.

[0025] Preferably, the length of the elastic tube is 20-30 mm.

[0026] Preferably, the base material of the bionic fixator includes any one or a combination of elastic latex, silicone, and polyurethane materials.

[0027] Preferably, the material of the catheter body includes any one or a combination of latex, rubber, polyvinyl chloride and polyurethane.

[0028] Furthermore, the bionic anti-viscosity and drag reduction structure includes:

[0029] A wedge-shaped protrusion structure comprising a plurality of wedge-shaped protrusion units arranged in an array on the inner wall of the urinary catheter main channel, each of the wedge-shaped protrusion units comprising one or more main inclined surfaces with an angle of less than 10° with the channel wall, the main inclined surfaces facing the flow direction of urine;

[0030] A corrugated protrusion structure comprising a plurality of corrugated protrusion units arranged in an array on the main inclined surface, wherein the sizes of the corrugated protrusion units and the wedge-shaped protrusion units are both in the micron order;

[0031] The hydrophobic super-slip coating is arranged on the inner wall of the main urinary catheterization channel.

[0032] The bionic anti-adhesion and drag reduction structure uses a wedge-shaped raised structure to mimic the characteristics of tarpon scales, and a corrugated raised structure to mimic the skirt of kelp. By combining the micron-level bionic anti-adhesion and drag reduction structure with the nano-level hydrophobic super-slip coating, synergistic anti-adhesion and drag reduction are achieved. The specific principles are as follows:

[0033] Grooves are formed between the micron-sized wedge-shaped protrusion units that are low in front and high in the back. When the fluid flows through the tail of the wedge-shaped protrusion unit, the fluid swirls to generate vortices, causing part of the fluid near the wedge-shaped protrusion unit to produce a non-zero initial velocity, promptly washing away the settled impurities and viscous fluid, and reducing the viscous resistance in the urine flow.

[0034] The wedge-shaped protrusion unit with a low front and a high back maintains a relatively high fluid contact angle front. At the same time, the corrugated protrusion structure increases the roughness of the inclined surface of the wedge-shaped protrusion unit. Combined with the hydrophobic effect of the hydrophobic coating, it further reduces the direct contact and viscosity of urine and impurities with the inner wall of the main catheterization channel. It can not only reduce the residue, adhesion or backflow of urine on the inner wall of the main catheterization channel, but also reduce adhesion friction, thereby reducing the energy loss of the fluid vortex, which is conducive to maintaining a stable fluid vortex and further enhancing the anti-viscosity and drag reduction effect.

[0035] Furthermore, the center distance between the adjacent wedge-shaped protrusion units is 1.0-2.0 times the length of the wall surface of the wedge-shaped protrusion unit along the fluid flow direction.

[0036] Preferably, the protrusion height of the wedge-shaped protrusion unit is 0.02-0.2 times the length of the wall-adhering surface.

[0037] Preferably, the protrusion height of the wedge-shaped protrusion unit is less than 0.5 mm.

[0038] Preferably, the shape of the wall-adhering surface of the wedge-shaped protrusion unit includes one or a combination of polygonal, circular, elliptical or fan-shaped, wherein the polygon includes triangle, quadrilateral and pentagon.

[0039] Preferably, a plurality of the wedge-shaped protrusion units form a planar array on the wall surface of the flow channel, and the arrangement of the array includes any one or a combination of square, rhombus, hexagonal and irregular arrays.

[0040] Preferably, the length of the wedge-shaped protrusion unit along the fluid flow direction is 0.5-5.0 mm, and the width along the circumferential direction of the flow channel wall is 0.1-1.0 mm.

[0041] When the wedge-shaped protrusions are too large, the inward convergence of the fluid from the previous wedge-shaped protrusion cannot be sustained to the next adjacent wedge-shaped protrusion, making it impossible to maintain a stable vortex to achieve anti-viscosity drag reduction. This results in an excessively large fluid boundary layer and increased drag. Similarly, when the spacing between adjacent wedge-shaped protrusions is too large, it is impossible to maintain a stable fluid vortex to flush away heavier impurities. The wedge-shaped protrusions cannot be used to adjust the flow field distribution and reduce the thickness of the turbulent layer, making it difficult to promptly flush away settled impurities and viscous fluids. Setting an appropriate angle between the inclined surface and the channel wall also helps maintain a stable fluid vortex.

[0042] Preferably, the waveform of the corrugated protrusion unit includes any one of a C-shape, a U-shape, an S-shape, a sawtooth shape, a sine waveform or an attenuated waveform, or a combination of several of them.

[0043] Preferably, the wave path of the corrugated protrusion unit is 0.5-100 wavelengths.

[0044] Preferably, the height of the corrugated protrusion unit is 0.1-10 times the wavelength of the corrugated protrusion unit.

[0045] Preferably, one or more of the corrugated protrusion units form the corrugated protrusion structure that is arranged horizontally, vertically or staggered at an oblique angle.

[0046] Preferably, the interval between adjacent corrugated protrusion units is 0.1-2 times the protrusion height of the corrugated protrusion units, and the sizes are all in micron order.

[0047] Preferably, the hydrophobic coating is a biocompatible hydrophobic flexible polymer molecular brush coating, and the thickness of the hydrophobic coating is 5-100 nm.

[0048] Preferably, the hydrophobic flexible polymer is selected from any one of polydimethylsiloxane, perfluoropolyether, polyisobutylene and their derivatives.

[0049] The present application also provides a method for using the above-mentioned anti-adhesion and drag-reducing urinary catheter with a bionic fixator, comprising the following steps:

[0050] Insert the catheter along the urethra to allow the bionic fixator to reach the urethra;

[0051] Gas or liquid is filled into the cavity between the elastic tube and the main catheterization channel through the inflation / liquid channel, and the inflation / liquid inlet is sealed in time. The bionic fixator will swell up with uneven surface deformation, supporting the micron-scale adhesion protrusion structure on the outer wall of the elastic tube to contact and adhere to the inner wall of the urethra, thereby fixing the bionic fixator in the urethra.

[0052] Preferably, the method further includes the following steps: before inserting the catheter into the urethra, applying a lubricant to the outside of the catheter, wherein the lubricant is any one or more of a silicone lubricant, a gel, a water-based lubricant, and a polyvinyl alcohol lubricant, and the catheter body and the bionic fixator do not react with the selected lubricant such as swelling.

[0053] In summary, this application includes at least one of the following beneficial technical effects:

[0054] 1. The bionic fixator provided in this application is fixed to the urethra, allowing some patients to continue to use the bladder and internal urethral sphincter to control urination, reducing the risk of bladder atrophy. Because the operation of inserting the bladder is avoided, the insertion length is short, which reduces foreign body stimulation to the bladder and helps prevent urinary reflux infection. At the same time, it fully drains urine from a position below the bladder, reducing the chance of clogging of the catheter port due to long-term immersion in bladder urine, thereby improving the safety and convenience of long-term indwelling catheterization.

[0055] 2. The biomimetic fixator provided in this application has a convex and concave surface, combined with the micron-scale adhesive protrusions on the outer wall that mimic a frog's foot, to achieve dual fixation, preventing catheter slippage and reducing urine leakage due to poorly fitting thin catheters. The fixation of the catheter in the urethra is independent of the catheter body's diameter, thus helping to avoid urethral damage and infection risks associated with frequent replacement of thicker catheters.

[0056] 3. The present application sets a bionic anti-adhesion and drag-reducing structure on the inner wall of the main catheterization channel of the catheter, fully imitating the surface characteristics of animals and plants such as silver carp and kelp that swing with low resistance in seawater and are not easily adhered to pollutants. It imitates the multi-level bionic anti-adhesion and drag-reducing structure that combines the structure and arrangement of silver carp scales, the corrugated structure of kelp skirts and the anti-adhesion and super-slip flexible coating. First, the urine flow field characteristics are changed by the micron-scale wedge-shaped protrusion structure, and the grooves between adjacent wedge-shaped protrusion units are used to generate fluid vortices to propel the flow, thereby promptly washing away settled impurities and viscous fluids, reducing the viscous resistance between fluids, and accelerating the low-resistance flow of urine along the catheter; at the same time, the micron-scale corrugated protrusion structure and nano-scale hydrophobic coating on the wedge-shaped protrusion structure exert a hydrophobic anti-viscosity and drag reduction effect, preventing the viscous deposition of urine, blood and stones, reducing the friction resistance in contact with the inner wall of the catheter, reducing the possibility of catheter blockage or even infection, effectively extending the service life of the catheter, reducing the risk of damage and infection to patients caused by frequent catheter replacement, and increasing the safety and convenience of long-term indwelling catheterization. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] Figure 1 This is a schematic diagram of the overall structure of an anti-adhesive and drag-reducing urinary catheter with a bionic fixator according to an embodiment of the present application;

[0058] Figure 2Schematic diagram of the elastic pipe deployment of the bionic fixator in the embodiment of the present application, wherein:

[0059] (a) is a schematic diagram of an elastic conduit using a smooth annular tube with a shaped band, (b) is a schematic diagram of an elastic conduit using an inner-hole conduit, (c) is the unfolded shape of the shaped band and the shaped channel, where the channel connectivity relies on multiple gas / liquid outlets, and (c-1)-(c-4) are schematic diagrams of annular, spiral, twill, and reticular shapes, respectively;

[0060] Figure 3 Schematic diagrams of the micron-scale adhesion protrusion structures on the outer wall of the biomimetic holdfast in an embodiment of the present application, wherein (a) is a schematic diagram of the outer wall of the biomimetic holdfast, (b) is an array of triangular prism adhesion protrusion structures, (c) is an array of quadrangular prism adhesion protrusion structures, (d) is an array of pentagonal prism adhesion protrusion structures, and (e) is an array of adhesion protrusion structures composed of hexagonal and triangular prisms;

[0061] Figure 4 The present invention is a schematic diagram mainly used to illustrate the arrangement of wedge-shaped protrusion units on the inner wall of the main urinary catheterization channel, wherein (a)-(c) are schematic diagrams of wedge-shaped protrusion units with triangular, quadrilateral, and pentagonal wall surfaces, respectively;

[0062] Figure 5 This is a cross-sectional schematic diagram of an embodiment of the present application mainly used to illustrate the arrangement of the wedge-shaped protrusion units on the inner wall of the urinary catheterization main channel;

[0063] Figure 6 Schematic diagrams of the structures of corrugated protrusion units of different shapes in the embodiments of the present application, wherein (a)-(f) are schematic diagrams of waveforms of C-shape, U-shape, S-shape, sawtooth shape, sinusoidal waveform or attenuated waveform, respectively;

[0064] Figure 7 This is a working effect diagram of the bionic fixator in the embodiment of the present application;

[0065] Figure 8 Schematic diagram of the anti-viscosity and drag reduction mechanism of the bionic anti-viscosity and drag reduction structure in the embodiment of the present application.

[0066] Figure numerals: 1. Bionic fixator; 1-1. Elastic tube; 1-2. Micron-scale adhesion protrusion structure; 1-3. Bundle belt; 1-4. Sealed chamber; 1-5. Bundle channel; 2. Bionic urinary catheter body; 2-1. Catheterization main channel; 2-2. Inflation / liquid channel; 2-3. Flushing and injection channel; 2-4. Catheterization port; 2-5. Inflation / liquid outlet; 2-6. Flushing and injection outlet; 2-7. Urine outlet; 2-8. Inflation / liquid inlet; 2-9. Flushing and injection inlet; 3. Bionic anti-adhesion and drag reduction structure; 3-1. Wedge-shaped protrusion structure; 3-2. Corrugated protrusion structure; 3-3. Hydrophobic super-slip coating. DETAILED DESCRIPTION

[0067] The following is combined with Figure 1-8 This application is described in further detail.

[0068] The present application discloses an anti-adhesion and drag-reducing urinary catheter with a bionic fixator. Figure 1 The urinary catheter includes a main body 2 and a bionic fixator 1. The main body 2 includes a main urinary catheterization channel 2-1, and a urinary catheterization port 2-4 and a urine outlet 2-7 are respectively opened at both ends of the main urinary catheterization channel 2-1. When in use, urine enters the main urinary catheterization channel 2-1 through the urinary catheterization port 2-4 and is then discharged from the urine outlet 2-7.

[0069] Reference Figure 1 The two sides of the main catheterization channel 2-1 are respectively provided with a flushing and injection channel 2-3 and an inflation / liquid channel 2-2, the two ends of the flushing and injection channel 2-3 are respectively provided with a flushing and injection inlet 2-9 and a flushing and injection outlet 2-6, and the two ends of the inflation / liquid channel 2-2 are respectively provided with an inflation / liquid inlet 2-8 and an inflation / liquid outlet 2-5.

[0070] Reference Figure 1 The biomimetic fixator 1 comprises an elastic tube 1-1 and micron-scale adhesive protrusions 1-2 disposed on the outer wall of the elastic tube 1-1. The inner diameter of the elastic tube 1-1 is 1 mm larger than the outer diameter of the catheter body 2. The elastic tube 1-1 is sleeved over the catheter body 2 and positioned near the catheter port 2-4. The inner walls of the elastic tube 1-1 at both ends are affixed to the outer wall of the catheter body 2, perhaps by bonding. This creates a sealed cavity between the elastic tube 1-1 and the catheter body 2. The air / liquid outlet 2-5 is located within the sealed cavity, connecting the sealed cavity to the air / liquid channel 2-2.

[0071] Reference Figure 2 The elastic pipe 1-1 can be an inner hole pipe or a smooth ring pipe with a bundled belt 1-3. Figure 2 As shown in (a), the shaped band 1-3 is set on the inner wall of the smooth ring tube or embedded in the wall of the smooth ring tube. The shaped band 1-3 includes multiple bands arranged in an array. The band is elastic and its elastic deformation is smaller than that of the smooth ring tube. The cavity between the inner wall of the band ring tube and the outer wall of the catheter body 2 is a closed chamber 1-4 connected to the inflation / liquid channel 2-2. Figure 2 As shown in (b), the inner wall of the inner tube is provided with bundled channels 1-5, which are connected to the gas / liquid channel 2-2. Furthermore, the shape of the bundled bands 1-3 or bundled channels 1-5 can be any one of vertical stripes, spirals, rings, diagonal stripes, or a reticular pattern, or a combination thereof.

[0072] Reference Figure 3The micron-scale adhesive protrusion structure 1-2 comprises a plurality of micron-scale adhesive protrusion units arranged in an array on the outer wall of the elastic tube 1-1. The micron-scale adhesive protrusion units are polygonal prisms and are elastic. The polygonal prisms can be any one of triangular prisms, quadrangular prisms, pentagonal prisms, hexagonal prisms, or a combination thereof, or can have a greater number of prisms.

[0073] In this embodiment, the elastic tube 1-1 of the biomimetic fixator 1 can be a smooth annular tube with a scalloped band. The length of the elastic tube 1-1 is 20 mm. The scalloped band 1-3 is a plurality of parallel vertically ridged bands, each 0.5 mm wide, with a 1 mm interval between adjacent bands. The micron-scale adhesive protrusion units 1-2 are regular hexagonal prisms with a protrusion height of 150 μm. The base of the regular hexagonal prism has a side length of 100 μm, the diameter of the circumscribed circle of the base is 200 μm, and the center-to-center spacing between adjacent regular hexagonal prisms is 250 μm.

[0074] Due to the difference in elasticity between the bundle band 1-3 and the smooth annular tube, or under the bundle effect of the bundle channel 1-5, the bionic fixator bulges with an uneven surface, and cooperates with the micron-level adhesive protrusion structure 1-2 on the outer wall of the elastic tube that imitates the feet of a frog to achieve double fixation, preventing the bionic fixator from slipping and reducing urine leakage due to the mismatch of thin catheters; the fixation of the catheter in the urethra does not depend on the diameter of the catheter body, which helps to avoid damage to the urethra and the risk of infection caused by frequent replacement of thick catheters.

[0075] Reference Figure 1 、 Figure 4 and Figure 5 The inner wall of the main urinary catheterization channel 2-1 is provided with a biomimetic anti-viscosity drag-reducing structure 3, which comprises a wedge-shaped protrusion structure 3-1, a corrugated protrusion structure 3-2, and a hydrophobic ultra-slip coating 3-3. The wedge-shaped protrusion structure 3-1 comprises a plurality of wedge-shaped protrusion units arranged in an array on the inner wall of the main urinary catheterization channel 2-1. Each wedge-shaped protrusion unit includes at least one main inclined surface with an angle of less than 10° with the channel wall and a wall-adhering surface that adheres to the channel wall. The main inclined surface faces the direction of fluid flow.

[0076] Reference Figure 4 The wall-adhering surface of the wedge-shaped protrusion unit is a polygon, which can be any one of a triangle, a quadrilateral, a pentagon, or a combination thereof, or other polygons. The wedge-shaped protrusion unit can be a polygonal pyramid or a polygonal prism truncated along the vertex.

[0077] Reference Figure 4 and Figure 5 In the direction of fluid flow, multiple wedge-shaped protrusion units are arranged in a fish-scale-like manner, with the front lower and the back higher, and grooves are formed between adjacent wedge-shaped protrusion units.

[0078] Taking a tetrahedral wedge-shaped protrusion unit design as an example, one side of the tetrahedral pyramid is the wall-adhering surface, and the side opposite to the wall-adhering surface is the inclined surface. The cross-section of the tetrahedral pyramid along the direction parallel to the flow channel is a triangle with an inclination angle of 5°. The height of the wedge-shaped protrusion unit is 0.4 mm, the width of the wedge-shaped protrusion unit is 0.9 mm, and the length is 4 mm. The center distance between the two adjacent tetrahedral pyramids is about 6 mm. They are arranged in a fish scale-like manner, with the front lower and the back higher, staggered on the inner wall of the main catheter channel. The arrangement method refers to Figure 4 (a) in the.

[0079] Reference Figure 1 、 Figure 4 and Figure 6 The corrugated protrusion structure 3-2 includes a plurality of corrugated protrusion units arranged in an array on an inclined surface. The corrugated protrusion units extend in the direction of fluid flow. The waveform of the corrugated protrusion units can be any one of a C-shape, a U-shape, an S-shape, a sawtooth shape, a sine wave shape, or a decaying wave shape, or a combination thereof.

[0080] As an example, S-shaped corrugated protrusion units with a wave path of 200-800 μm are evenly distributed on the inclined surface of the wedge-shaped protrusion unit along the direction of urine flow, the spacing between adjacent corrugated protrusion units is 20 μm, and the height of the corrugated protrusion unit is 80 μm.

[0081] Reference Figure 1 The bionic anti-viscosity and drag-reducing structure 3 further includes a hydrophobic coating 3-3 coated on the inner wall of the main urinary catheter channel 2-1. The hydrophobic coating 3-3 is a biocompatible hydrophobic flexible polymer molecular brush coating with a thickness of 5-100 nm.

[0082] In this embodiment, the bionic fixator 1 is formed by injecting a latex material into a mold having micron-scale adhesive protrusion structures 1-2, followed by molding and cutting. The catheter body 2 is made of silicone rubber and manufactured using extrusion and injection molding processes. A uniformly mixed silicone raw material is injected into the outer mold of the catheter body 2, and then an inner mold having a bionic anti-stick and drag-reducing structure is inserted and extruded to fully replicate the bionic anti-stick and drag-reducing structure, thereby obtaining the catheter body 2. The catheter body 2 is provided with a catheter port 2-4, an air / liquid outlet 2-5, and an irrigation and injection outlet 2-6. The bionic fixator 1 is placed over the catheter body 2, and then the ends of the elastic tube 1-1 in the bionic fixator 1 are bonded to the outer wall of the catheter body 2.

[0083] After the catheter is pretreated with oxygen plasma, the inner and outer surfaces are repeatedly dipped in a biocompatible hydrophobic polydimethylsiloxane solution. A high-density hydrophobic polymer molecular brush coating with a thickness of 5-100 nm is grafted onto it through covalent bonds. The high flexibility and low chemical bond rotation energy of the polydimethylsiloxane molecular chain maintain the surface's ultra-slip properties (ultra-low dynamic contact hysteresis angle CAH or Δθ < 5°) and give the surface good lipophilic and hydrophobic properties (θ 油 <90°, θ 水 >90°).

[0084] When using, first apply a proper amount of silicone oil lubricant on the outer wall of the catheter, then insert the catheter along the urethra, so that the bionic fixator 1 reaches the middle part of the urethra. Figure 7 As shown, an appropriate amount of air or sterile saline is injected into the sealed cavity between the elastic tube 1-2 and the catheter body 2 through the air / liquid channel 2-2. The elastic tube 1-2 swells into a shaped, uneven balloon, causing the micron-sized adhesive protrusions on the outer wall of the elastic tube 1-2 to prop up and adhere to the inner wall of the urethra, thereby securing the bionic fixator 1 in the urethra. This not only helps control urination and reduce bladder infections through the bladder and internal urethral sphincter, but also reduces insertion length through good contact between the bionic fixator and the urethra, preventing urine leakage and catheter movement, thereby improving the safety and convenience of long-term indwelling catheterization.

[0085] The principle of the bionic anti-viscosity and drag reduction structure 3 on the inner wall of the main catheter channel 2-1 is as follows: Figure 8 As shown, the details are as follows:

[0086] Grooves are formed between the micron-sized wedge-shaped protrusions, which are low in front and high in the back. When the fluid flows through the tail of the wedge-shaped protrusion, the fluid swirls to generate vortices, causing the part of the fluid near the wedge-shaped protrusion to generate a non-zero initial velocity, promptly washing away the settled impurities and viscous fluid, and reducing the viscous resistance inside the fluid. At the same time, the wedge-shaped protrusions, which are low in front and high in the back, keep the fluid at a high contact angle front. The micron-sized corrugated protrusion structure increases the roughness of the main inclined surface of the wedge-shaped protrusion. Combined with the hydrophobic coating, it further enhances the super-slip anti-stick properties, reduces the thickness of the fluid boundary layer, and reduces the direct contact and adhesion of the fluid and impurities with the channel wall, thereby reducing the frictional resistance between the fluid and the wall. This not only reduces the residual, adhesion or backflow of the fluid on the channel wall, achieving anti-stick drag reduction when the fluid and impurities contact the channel wall, but also reduces viscous friction, thereby reducing the energy loss of the fluid vortex, which is conducive to maintaining a stable fluid vortex and further enhancing the anti-stick effect.

[0087] The above are all preferred embodiments of the present application, and are not intended to limit the scope of protection of the present application. Therefore, any equivalent changes made based on the structure, shape, and principle of the present application should be included in the scope of protection of the present application.

Claims

1. An anti-adhesive and drag-reducing urinary catheter with a bionic fixator, characterized by: It includes a urinary catheter body and a bionic fixator arranged on the urinary catheter body; The catheter body includes a main catheterization channel and an air / liquid channel; the inner wall of the main catheterization channel is provided with a bionic anti-viscosity and drag reduction structure for reducing the viscosity and friction of urine on the inner wall of the main catheterization channel; The bionic fixator includes an elastic tube and a micron-scale adhesive protrusion structure; The elastic tube is located at the head and neck of the catheter body, the cavity between the elastic tube and the catheter body is connected to the inflation / liquid channel, and is sealed at the air / liquid inlet of the inflation / liquid channel; The micron-scale adhesion protrusion structure includes a plurality of micron-scale adhesion protrusion units arranged in an array on the outer wall of the elastic tube; When the elastic tube bulges and deforms, the micron-scale adhesion protrusion structure on the outer wall is supported, so that the bionic fixator forms contact and adhesion with the urethra; The bionic anti-viscosity and drag reduction structure comprises: A wedge-shaped protrusion structure comprising a plurality of wedge-shaped protrusion units arranged in an array and attached to the wall of the flow channel, each of the wedge-shaped protrusion units comprising one or more main inclined surfaces with an angle of less than 10° with the wall of the flow channel, the main inclined surfaces facing the flow direction of the fluid; A corrugated protrusion structure comprising a plurality of corrugated protrusion units arranged in an array on the main inclined surface, wherein the sizes of the corrugated protrusion units and the wedge-shaped protrusion units are both in the micron order; A hydrophobic super-slip coating is provided on the wall surface of the flow channel.

2. The anti-adhesion and drag-reducing urinary catheter with a bionic fixator according to claim 1, characterized in that: The elastic pipe is a banded ring pipe or an inner hole pipe, wherein: The banded ring tube is a smooth ring tube with a band arranged inside the wall. The elastic deformation of the band is smaller than that of the smooth ring tube. The cavity between the inner wall of the banded ring tube and the outer wall of the urinary catheter body is a closed chamber connected to the inflation / liquid channel. A bundle-shaped channel is provided inside the wall surface of the inner bore pipe, and the bundle-shaped channel is communicated with the gas / liquid channel.

3. The anti-adhesion and drag-reducing urinary catheter with a bionic fixator according to claim 2, characterized in that: The unfolded structure of the bundle includes any one of vertical stripes, spiral stripes, ring stripes, diagonal stripes, and mesh stripes, or a combination of several of them.

4. The anti-adhesion and drag-reducing urinary catheter with a bionic fixator according to claim 2, characterized in that: The bundled channels include any one of vertical, spiral, annular, diagonal, and mesh channels or a combination of these channels that are interconnected.

5. The anti-adhesion and drag-reducing urinary catheter with a bionic fixator according to claim 2, characterized in that: After the bionic fixator is filled with gas or liquid, the presence of the bundle-shaped belt or the bundle-shaped channel causes the elastic tube to deform with an uneven surface.

6. The anti-adhesion and drag-reducing urinary catheter with a bionic fixator according to claim 1, characterized in that: The micron-scale adhesion protrusion unit is a polygonal prism, and the height of the micron-scale adhesion protrusion unit is 0.1-2.0 times the diameter of the circumscribed circle of the bottom surface of the polygonal prism.

7. The anti-adhesion and drag-reducing urinary catheter with a bionic fixator according to claim 6, characterized in that: The center distance between adjacent micron-sized adhesion protrusion units is 1.0-2.0 times the diameter of the circumscribed circle of the bottom surface of the polygonal prism.

8. The anti-adhesion and drag-reducing urinary catheter with a bionic fixator according to claim 1, characterized in that: The center distance between the front and rear adjacent wedge-shaped protrusion units is 1.0-2.0 times the length of the wall-adhering surface of the wedge-shaped protrusion unit along the fluid flow direction.

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