Surface-modified polyether ether ketone materials, methods of making and uses thereof

Abstract

The application discloses a surface modified polyether ether ketone material and a preparation method and application thereof. The preparation method of the surface modified polyether ether ketone material comprises the following steps: 1) etching the surface of polyether ether ketone by a femtosecond laser to form regularly arranged protrusions, and obtaining a patterned polyether ether ketone; 2) activating the surface of the patterned polyether ether ketone by nitrogen gas source plasma immersion ion implantation under vacuum conditions, and obtaining an activated polyether ether ketone; and 3) coating the surface of the activated polyether ether ketone with a bioactive solution, and obtaining the surface modified polyether ether ketone material. The preparation method can make the obtained surface modified polyether ether ketone material have a smaller minimum water contact angle, and significantly reduce the biological inertness of the surface of the polyether ether ketone.

Description

Technical Field

[0001] This invention relates to a surface-modified polyether ether ketone material, its preparation method, and its uses. Background Technology

[0002] Polyether ether ketone (PEEK) is a high-performance specialty engineering plastic that has shown broad application prospects in the biomedical field due to its excellent mechanical properties, good biocompatibility, chemical resistance, radiation permeability, and thermal stability. However, pure PEEK material has low surface energy, is strongly hydrophobic, and is inherently bioinert, lacking osteoconductive and osteoinductive activity. After implantation, it is difficult to form stable chemical bonds with host bone tissue, and it easily forms a fibrous encapsulation layer at the interface, resulting in low osseointegration efficiency, poor long-term fixation, and even implant failure due to implant micromovement and infection of surrounding tissues. This restricts the further application of PEEK in demanding bone repair scenarios. How to improve the hydrophilicity of PEEK surface and reduce its bioinertness has become an urgent technical problem to be solved in this field.

[0003] CN119870690A discloses a surface treatment method for orthopedic implants based on femtosecond lasers. This surface treatment method includes the following steps: S1: cleaning and drying the surface of the orthopedic implant substrate; S2: performing femtosecond laser treatment on the surface of the orthopedic implant substrate to form regularly arranged microstructures on the substrate surface; wherein, the orthopedic implant substrate includes a metal substrate, a bioceramic substrate, and a polymer material substrate; the polymer material substrate includes a polyetheretherketone (PEEK) substrate; the microstructure includes one or more of grooves, lattices, or meshes; S3: applying a plasma-sprayed bio-coating to the femtosecond laser-treated orthopedic implant substrate surface to finally obtain a surface-modified orthopedic implant. Although this surface treatment method can improve the bonding force between the bio-coating and PEEK, the direct plasma-spraying of the bio-coating onto the femtosecond laser-treated orthopedic implant substrate surface results in a short period of hydrophilicity in the obtained orthopedic implant surface, which easily reverts to bioinertness. Furthermore, the metal elements used in this surface treatment method mainly have antibacterial and anti-inflammatory effects, and the effect of metal ions in inducing bone regeneration is very limited.

[0004] CN120939286A discloses a time-degradable orthopedic implant material. This time-degradable orthopedic implant material includes a substrate and a biodegradable coating formed on the surface of the substrate; the substrate surface has a nanocone array microstructure; the biodegradable coating uses a biodegradable polymer as a matrix and loads metal elements that promote bone repair; the surface of the biodegradable coating is also linked to anti-inflammatory active factors. The nanocone array microstructure on the substrate surface is obtained by plasma etching. Plasma etching can only produce shallow depressions on the substrate surface, and the effect of modifying the substrate surface is short-lived. Furthermore, during the preparation of this orthopedic implant material, oxygen-source gas plasma immersion ion implantation technology is used to activate the surface of the composite material and graft anti-inflammatory active factors. This activation method only increases the surface roughness of the composite material and cannot form chemical bonds. Therefore, the combination of the composite material and the anti-inflammatory active factors is a physical bond, and the strength is not ideal. Summary of the Invention

[0005] In view of this, one object of the present invention is to provide a method for preparing a surface-modified polyetheretherketone (PEEK) material, wherein the surface-modified PEEK material obtained by this method has a small minimum water contact angle and the surface modification state can be maintained for a longer period of time. Another object of the present invention is to provide a surface-modified PEEK material obtained by the above-described preparation method. A further object of the present invention is to provide uses for the above-described surface-modified PEEK material.

[0006] The present invention achieves the above objectives using the following technical solutions.

[0007] On one hand, the present invention provides a method for preparing a surface-modified polyetheretherketone material, comprising the following steps: 1) Patterned polyetheretherketone (PEEK) is obtained by etching regularly arranged protrusions on its surface using a femtosecond laser; wherein the protrusions are in the shape of a regular frustum. 2) The patterned polyether ether ketone surface is activated under vacuum conditions by nitrogen-sourced plasma immersion ion implantation to obtain activated polyether ether ketone; 3) The surface of activated polyetheretherketone is coated with a bioactive solution to obtain a surface-modified polyetheretherketone material; wherein, the solute of the bioactive solution is a biodegradable polyester and a bioactive substance; the biodegradable polyester is selected from at least one of poly(L-lactic acid), polyglycolic acid, polyglycolic acid, polycaprolactone, and polyhydroxyalkanoates, and the bioactive substance is selected from at least one of bioactive glass, calcium phosphate-based bioceramics, and hydroxyapatite; in the bioactive solution, based on 100 mL of solvent, the amount of biodegradable polyester is 1-20 g, and the amount of bioactive substance is 5-50 g.

[0008] According to the preparation method of the present invention, preferably, in step 1), the protrusion is a regular square frustum, the upper base side length of the regular square frustum is 5-50 μm, the lower base side length is 20-100 μm, and the height is 5-50 μm; The distance between two adjacent protrusions is 10 to 100 μm.

[0009] According to the preparation method of the present invention, preferably, in step 1), the control parameters of the femtosecond laser are as follows: The linearly polarized light has a center wavelength of 200–500 nm, a spot diameter of 5–30 μm, a spot overlap rate of 30–95%, a pulse width of 50–200 fs, and an output power of 20–80 mW; the scanning speed is 5–50 mm / s, the scanning interval is 20–50 μm, and the number of scans is 2–8.

[0010] According to the preparation method of the present invention, preferably, in step 2), the vacuum degree of the vacuum condition is 0.5 × 10⁻⁶. -3 ~5×10 -3 Pa.

[0011] According to the preparation method of the present invention, preferably, in step 2), the control parameters for the nitrogen source plasma immersion ion implantation are as follows: The implantation voltage is -5 to -50 kV, the radio frequency power is 100 to 300 W, the pulse width is 5 to 60 μs, the pulse frequency is 20 to 100 Hz, and the ion implantation time is 10 to 60 min.

[0012] According to the preparation method of the present invention, preferably, in step 3), the coating is dip coating.

[0013] According to the preparation method of the present invention, preferably, in step 3), the number of dip coatings is 1 to 5; wherein, the soaking time for each dip coating is 10 to 60 seconds, and the pull-out speed for each dip coating is 1 to 10 mm / min.

[0014] According to the preparation method of the present invention, in step 3), the solvent is selected from at least one of dichloromethane, hexafluoroisopropanol, N-methylpyrrolidone, tetrahydrofuran, dimethylformamide, dimethyl sulfoxide, and trifluoroethanol.

[0015] On the other hand, the present invention also provides a surface-modified polyetheretherketone (PEEK) material prepared by any of the above-described preparation methods. The surface-modified PEEK material has a minimum water contact angle of 78° or less, and the minimum water contact angle is maintained for at least 25 days.

[0016] In another aspect, the present invention also provides the use of the above-mentioned surface-modified polyetheretherketone material in the preparation of orthopedic implants.

[0017] This invention utilizes a combination of femtosecond laser and nitrogen-sourced plasma immersion ion implantation to synergistically treat the surface of polyetheretherketone (PEEK), and then coats the PEEK surface with a bioactive substance. This results in a surface-modified PEEK material with a small minimum water contact angle, significantly reducing the bioinertness of the PEEK surface. Furthermore, the surface-modified PEEK material of this invention can maintain its modified state for a relatively long period. Attached Figure Description

[0019] Figure 1 This is a flowchart illustrating the preparation process of surface-modified polyetheretherketone (PEEK) materials according to an embodiment of the present invention.

[0020] Figure 2 This is a schematic diagram of a cross-section of the protrusion along a direction perpendicular to the side length of the bottom surface, according to an embodiment of the present invention.

[0021] Figure 3 The images shown are microscopic images and contour images of the protrusions in the surface-modified polyether ether ketone material according to an embodiment of the present invention; wherein, image A is a microscopic image of the protrusion under low magnification, image B is a magnified image of the image within the frame in image A under high magnification, and image C is a contour image of the protrusion.

[0022] Figure 4 This is the minimum water contact angle of the polyetheretherketone material in Experimental Example 2 of this invention.

[0023] Figure 5 This refers to the water contact angle of the polyetheretherketone material in Experimental Example 3 of this invention.

[0024] Figure 6 The cell viability is represented by each group of polyetheretherketone materials in Experimental Example 4 of this invention. Detailed Implementation

[0026] The present invention will be further described below with reference to specific embodiments, but the scope of protection of the present invention is not limited thereto.

[0027] The "water contact angle" mentioned in this invention refers to the angle between the tangent of the gas-liquid interface and the solid-liquid interface at the junction of the gas, liquid, and solid phases, and is expressed in degrees (°).

[0028] The "minimum water contact angle" mentioned in this invention refers to the water contact angle measured within 30 minutes after the surface-modified polyether ether ketone material is prepared.

[0029] The "vacuum degree" mentioned in this invention refers to the absolute vacuum degree; the smaller the value, the higher the vacuum degree.

[0030] <Preparation Method of Surface-Modified Polyetheretherketone Materials> The periosteum is a dense connective tissue membrane covering the bone surface except for the articular surfaces. It not only participates in the nutritional supply, mechanical support, and nerve sensation of bone tissue, but also plays a crucial role in bone growth, fracture repair, and bone remodeling. It is an important physiological structure for promoting bone regeneration and achieving bone-implant interface integration. Inspired by the function of the periosteum, this invention innovatively provides a method for preparing surface-modified polyetheretherketone (PEEK) materials.

[0031] This invention provides a method for preparing a surface-modified polyetheretherketone (PEEK) material, comprising a PEEK patterning step, a PEEK activation step, and a bioactive solution coating step. The method is described in detail below.

[0032] Polyetheretherketone (PEEK) patterning steps Patterned polyetheretherketone (PEEK) is obtained by etching regularly arranged protrusions on its surface using a femtosecond laser.

[0033] In this invention, the protrusion can be a regular frustum. According to a preferred embodiment of the invention, the protrusion can be a regular square frustum. The upper base side length of the regular square frustum can be 5–50 μm, preferably 10–45 μm, more preferably 15–40 μm. The lower base side length of the regular square frustum can be 20–100 μm, preferably 30–85 μm, more preferably 40–70 μm. The height of the regular square frustum can be 5–50 μm, preferably 10–40 μm, more preferably 15–35 μm. According to a preferred embodiment of the invention, the distance between two adjacent protrusions can be 10–100 μm, preferably 20–80 μm, more preferably 35–60 μm. Such protrusions can achieve a larger specific surface area, increase the roughness of the polyetheretherketone (PEEK) surface, provide a uniformly distributed adhesion point for coating with bioactive solutions, reduce the water contact angle of the PEEK surface, increase the hydrophilicity of the PEEK surface, reduce the bioinertness of the PEEK surface, and ensure that the modified state of the PEEK surface is maintained for a longer period of time.

[0034] According to one embodiment of the present invention, the control parameters of the femtosecond laser are as follows: The center wavelength of the linearly polarized light can be 200–500 nm, preferably 240–450 nm, and more preferably 300–400 nm. The spot diameter can be 5–30 μm, preferably 7–24 μm, and more preferably 8–16 μm. The spot overlap rate can be 30–95%, preferably 45–90%, and more preferably 60–85%. The pulse width can be 50–200 fs, preferably 75–160 fs, and more preferably 85–120 fs. The output power can be 20–80 mW, preferably 30–70 mW, and more preferably 40–60 mW. The scanning speed can be 5–50 mm / s, preferably 10–40 mm / s, and more preferably 12–35 mm / s. The scanning spacing can be 20–50 μm, preferably 25–45 μm, and more preferably 30–40 μm. The number of scans can be 2–8, preferably 3–6, and more preferably 3–5.

[0035] Limiting the control parameters of the femtosecond laser to the above range is beneficial for precisely etching protrusions on the polyetheretherketone (PEEK) surface, reducing the water contact angle of the PEEK surface, increasing the hydrophilicity of the PEEK surface, reducing the bioinertness of the PEEK surface, and ensuring that the modified state of the PEEK surface is maintained for a longer period of time.

[0036] In this invention, femtosecond lasers can be generated by any femtosecond laser known in the art, without any particular limitation. For example, it can be a femtosecond laser micro / nano fabrication system.

[0037] According to a preferred embodiment of the present invention, the polyetheretherketone (PEEK) can be cleaned and dried before etching, and then femtosecond laser etching can be performed. This helps to remove impurities from the PEEK surface and avoids impurities interfering with the etching accuracy and effect. Cleaning can be performed using methods known in the art, and is not particularly limited here. For example, the PEEK can be ultrasonically cleaned in water, and then ultrasonically cleaned again in a 75 vol% ethanol aqueous solution. The power of each ultrasonic cleaning can be 200–1000 W, preferably 350–900 W, more preferably 400–850 W. The time for each ultrasonic cleaning can be 1–10 min, preferably 2–8 min, more preferably 3–7 min.

[0038] According to a preferred embodiment of the present invention, the patterned polyetheretherketone (PEEK) can also be cleaned and dried after etching. This facilitates the removal of PEEK residues and other impurities generated during etching, avoiding interference with subsequent activation and coating. Cleaning can be performed using methods known in the art, and is not particularly limited herein. For example, PEEK can be ultrasonically cleaned by immersing it in a 75 vol% ethanol aqueous solution. The ultrasonic cleaning power can be 200–1000 W, preferably 350–900 W, more preferably 400–850 W. The ultrasonic cleaning time can be 1–10 min, preferably 2–8 min, more preferably 3–7 min.

[0039] In this invention, drying can be achieved using any drying method and apparatus known in the art, and no particular limitation is made herein. For example, an oven can be used for drying. According to a preferred embodiment of the invention, the drying temperature can be 50–120°C, preferably 60–100°C, more preferably 65–90°C. The drying time can be 5–24 hours, preferably 8–20 hours, more preferably 10–15 hours.

[0040] The water used in each step of the present invention can be selected from at least one of deionized water, ultrapure water, reverse osmosis water, and triple-distilled water, preferably at least one of deionized water and ultrapure water, and more preferably deionized water or ultrapure water.

[0041] Polyetheretherketone Activation Steps The patterned polyether ether ketone surface was activated under vacuum conditions by nitrogen-sourced plasma immersion ion implantation to obtain activated polyether ether ketone.

[0042] According to one embodiment of the present invention, the vacuum degree of the vacuum condition can be 0.5 × 10⁻⁶. -3 ~5×10 -3 Pa, preferably 1×10 -3 ~4×10 -3 Pa, more preferably 1.5 × 10 Pa -3 ~3×10 -3 Pa. According to a preferred embodiment of the present invention, the stabilization time under vacuum before activation can be 5 to 30 minutes, preferably 7 to 25 minutes, and more preferably 8 to 15 minutes.

[0043] According to one embodiment of the present invention, the control parameters for nitrogen-sourced plasma immersion ion implantation are as follows: The implantation voltage can be -5 to -50 kV, preferably -10 to -40 kV, and more preferably -15 to -35 kV. The radio frequency power can be 100 to 300 W, preferably 120 to 280 W, and more preferably 150 to 220 W. The pulse width can be 5 to 60 μs, preferably 10 to 50 μs, and more preferably 15 to 45 μs. The pulse frequency can be 20 to 100 Hz, preferably 25 to 85 Hz, and more preferably 30 to 75 Hz. The ion implantation time can be 10 to 60 min, preferably 12 to 50 min, and more preferably 15 to 40 min.

[0044] According to a preferred embodiment of the present invention, the purity of nitrogen gas can be at least 99.99 vol%, preferably at least 99.995 vol%, and more preferably at least 99.999 vol.

[0045] Limiting the control parameters of nitrogen-sourced plasma immersion ion implantation to the above range is beneficial for introducing active groups such as -NHx and -CN onto the surface of patterned polyetheretherketone (PEEK). These active groups can form non-covalent chemical bonds (e.g., hydrogen bonds) or covalent chemical bonds (e.g., amide bonds) with -CO in the biodegradable polyester during subsequent coating, thereby making the coating more stable. This is more conducive to reducing the water contact angle of the PEEK surface, increasing the hydrophilicity of the PEEK surface, reducing the bioinertness of the PEEK surface, and ensuring that the modified state of the PEEK surface is maintained for a longer period of time.

[0046] In this invention, the nitrogen source plasma immersion ion implantation can be any type of plasma immersion ion implanter known in the art, and no particular limitation is made here.

[0047] Bioactive solution coating step A bioactive solution is coated onto the surface of activated polyether ether ketone to obtain a surface-modified polyether ether ketone material.

[0048] According to one embodiment of the present invention, the solute of the bioactive solution is a biodegradable polyester and a bioactive substance. The biodegradable polyester may be selected from at least one of poly(L-lactic acid), polyglycolic acid, polyglycolic acid, polycaprolactone, and polyhydroxyalkanoates, preferably at least one of poly(L-lactic acid), polyglycolic acid, polyglycolic acid, and polyglycolic acid, and more preferably at least one of poly(L-lactic acid), polyglycolic acid, and polyglycolic acid. According to one embodiment of the present invention, the molar ratio of glycolide to lactide in the polyglycolic acid may be 10–80:20–90, preferably 20–70:30–80, and more preferably 30–60:40–70.

[0049] In this invention, the intrinsic viscosity of the biodegradable polyester can be 1 to 2 dL / g, preferably 1.2 to 1.8 dL / g, and more preferably 1.3 to 1.6 dL / g.

[0050] According to one embodiment of the present invention, based on 100 mL of solvent, the amount of biodegradable polyester used can be 1 to 20 g, preferably 2 to 15 g, and more preferably 3 to 12 g.

[0051] Reasonable biodegradable polyester and dosage can ensure that a coating with good adhesion is formed on the polyetheretherketone surface after coating, and can ensure that a relatively stable chemical bond is formed with the activated groups on the activated polyetheretherketone surface, thereby helping to reduce the water contact angle of the polyetheretherketone surface, increase the hydrophilicity of the polyetheretherketone surface, and reduce the bioinertness of the polyetheretherketone surface.

[0052] According to one embodiment of the present invention, the bioactive substance may be selected from at least one of bioactive glass, calcium phosphate-based bioceramics, and hydroxyapatite, preferably at least one of bioactive glass and hydroxyapatite, and more preferably bioactive glass or hydroxyapatite. According to a preferred embodiment of the present invention, the bioactive glass may be any known type. For example, it may be selected from at least one of 45S5 bioactive glass, S53P4 bioactive glass, 58S bioactive glass, 13-93 bioactive glass, apatite-wollastonite bioactive glass, and Ceravital bioactive glass, preferably at least one of 45S5 bioactive glass, S53P4 bioactive glass, 58S bioactive glass, and apatite-wollastonite bioactive glass, and more preferably at least one of 45S5 bioactive glass, S53P4 bioactive glass, and apatite-wollastonite bioactive glass.

[0053] According to one embodiment of the present invention, in the bioactive solution, based on 100 mL of solvent, the amount of bioactive substance can be 5 to 50 g, preferably 10 to 40 g, and more preferably 15 to 35 g.

[0054] Appropriate bioactive substances and dosages can enhance the bioactivity of the coated polyether ether ketone surface, which is beneficial for inducing bone regeneration components and promoting cell adhesion and proliferation in practical applications.

[0055] According to one embodiment of the present invention, the solvent may be selected from at least one of dichloromethane, hexafluoroisopropanol, N-methylpyrrolidone, tetrahydrofuran, dimethylformamide, dimethyl sulfoxide, and trifluoroethanol, preferably at least one of dichloromethane, hexafluoroisopropanol, N-methylpyrrolidone, tetrahydrofuran, and dimethyl sulfoxide, and more preferably at least one of dichloromethane and hexafluoroisopropanol.

[0056] In this invention, the preparation method of the bioactive solution can be implemented using any method known in the art. According to a preferred embodiment of the invention, the preparation method of the bioactive solution may include stirring and dissolving, and ultrasonic dispersion steps. The stirring speed can be 200–800 rpm, preferably 250–700 rpm, more preferably 300–600 rpm. The stirring time can be 0.5–5 h, preferably 0.75–4 h, more preferably 1–3 h. The ultrasonic dispersion power can be 200–1000 W, preferably 350–900 W, more preferably 400–850 W. The ultrasonic dispersion time can be 5–30 min, preferably 6–25 min, more preferably 8–20 min.

[0057] According to one embodiment of the present invention, the coating can be achieved using any coating method known in the art. According to a preferred embodiment of the present invention, the coating method can be dip coating.

[0058] In this invention, the number of dip coatings can be 1 to 5 times, preferably 2 to 5 times, and more preferably 2 to 4 times. The immersion time for each dip coating can be 10 to 60 seconds, preferably 12 to 50 seconds, and more preferably 15 to 40 seconds. The pull-out speed for each dip coating can be 1 to 10 mm / min, preferably 2 to 8 mm / min, and more preferably 3 to 7 mm / min. Such dip coating conditions facilitate a more uniform and stable coating of the bioactive solution onto the surface of the activated polyetheretherketone (PEEK), further reduce the water contact angle of the PEEK surface, increase the hydrophilicity of the PEEK surface, and reduce the bioinertness of the PEEK surface.

[0059] In this invention, polyether ether ketone can be allowed to air dry after each dip coating before the next dip coating is performed, which helps to achieve a more uniform coating.

[0060] According to one embodiment of the present invention, the surface-modified polyetheretherketone (PEEK) material obtained after coating can be dried, which is more conducive to the formation of a stable coating on the activated PEEK surface by the bioactive solution. Drying can be achieved using any drying method and apparatus known in the art, and is not particularly limited herein. For example, an oven can be used for drying. According to a preferred embodiment of the present invention, the drying temperature can be 40–100°C, preferably 45–90°C, more preferably 50–85°C. The drying time can be 5–24 hours, preferably 8–20 hours, more preferably 10–15 hours.

[0061] <Surface-Modified Polyetheretherketone Materials> The present invention also provides a surface-modified polyetheretherketone material prepared by the above preparation method.

[0062] According to one embodiment of the present invention, the minimum water contact angle of the surface-modified polyetheretherketone (PEEK) material can be less than or equal to 78°, preferably less than or equal to 76°, and more preferably less than or equal to 75°. The retention time of the minimum water contact angle can be at least 25 days, preferably at least 27 days, and more preferably at least 28 days. The surface-modified PEEK material of the present invention has a small minimum water contact angle, significantly reduced surface bioinertness, and the modified state of the surface can be maintained for a longer period of time.

[0063] <Uses> The present invention also provides the use of the above-mentioned surface-modified polyetheretherketone material in the preparation of orthopedic implants.

[0064] In this invention, the orthopedic implant can be any of those known in the art. For example, it can be a fracture fixation implant (bone plate, bone screw, fixation frame, etc.), or at least one of artificial joints, spinal implants, and bone defect repair implants.

[0065] In the surface-modified polyether ether ketone material of the present invention, the biodegradable polyester can induce tissue fiber regeneration, and the bioactive substances can induce bone regeneration, thereby giving the surface-modified polyether ether ketone material of the present invention the function of inducing tissue regeneration of the periosteum, which is very advantageous as a material for orthopedic implants.

[0066] <Test Method> Contact angle measurement: The SZ-CAMB3 static contact angle tester from Shanghai Xuanzhun Instrument Co., Ltd. was used.

[0067] Microstructure and profile determination of polyetheretherketone surface: The determination was performed using an Olympus LEXT OLS5100 3D laser confocal microscope.

[0068] Absorbance was measured using a Bio-Rad 550 microplate reader from Bio-Rad Laboratories, USA.

[0069] <Partial Raw Material and Equipment Description> Unless otherwise specified, all raw materials used in the following examples are commercially available products.

[0070] The polyetheretherketone (PEEK) was purchased from Solvay, with the product number KT-820; it is in the form of a disc, with a diameter of 10 mm and a thickness of 1 mm.

[0071] Poly-L-lactic acid (PLLA) was purchased from Chengdu Meiyi Boya Materials Technology Co., Ltd., with an intrinsic viscosity of 1.3–1.6 dL / g.

[0072] Polyglycolic acid (PGA) was purchased from Chengdu Meiyi Boya Materials Technology Co., Ltd., and its intrinsic viscosity was 1.3-1.6 dL / g.

[0073] Poly(glycolic acid) lactide (PLGA) was purchased from Chengdu Meiyi Boya Materials Technology Co., Ltd., wherein the molar ratio of glycolide to lactide was 50:50 and the intrinsic viscosity was 1.3 to 1.6 dL / g.

[0074] 45S5 bioactive glass powder (BG) was purchased from Chengdu Meiyi Boya Materials Technology Co., Ltd.

[0075] The femtosecond laser micro / nano fabrication system was purchased from Workshop of Photonics, model FemtoLAB.

[0076] The plasma immersion ion implantation device was purchased from Beijing Borui Tiancheng Technology Co., Ltd., model BPF1.

[0077] Example 1 (1) Place the polyether ether ketone (referred to as PEEK sample) in deionized water and ultrasonically clean it for 5 min at a power of 600 W. Then, place the polyether ether ketone in an aqueous ethanol solution with a volume concentration of 75 vol% and ultrasonically clean it for 5 min at a power of 600 W. Then, place the PEEK sample in an oven and dry it at 80 °C for 12 h.

[0078] The protrusions of a regular square frustum were designed using AutoCAD software. Specific parameters are as follows: the upper base of the square frustum is 30μm, the lower base is 60μm, and the height is 20μm; the distance between two adjacent protrusions is 40μm. For example... Figure 2 As shown, the cross section of this regular square frustum along the direction perpendicular to the side length of the base is an isosceles trapezoid.

[0079] The dried PEEK sample was fixed on the sample stage of the femtosecond laser micro / nano processing system. The position of the PEEK sample was adjusted so that the laser focus was aligned with the surface of the PEEK sample. The parameters of the previously designed square frustum protrusion were imported, and the femtosecond laser parameters were set as follows: linearly polarized light center wavelength of 343 nm, spot diameter of 10 μm, spot overlap rate of 80%, pulse width of 100 fs, output power of 50 mW, scanning speed of 20 mm / s, scanning interval of 35 μm, and number of scans of 3. Using the aforementioned protrusion parameters and femtosecond laser parameters, the surface of the dried PEEK sample was etched to obtain patterned polyetheretherketone (PEEK).

[0080] The patterned polyether ether ketone was placed in a 75 vol% ethanol aqueous solution and ultrasonically cleaned for 5 min at a power of 600 W. Then the patterned polyether ether ketone was placed in an oven and dried at 80 °C for 12 h.

[0081] (2) The patterned polyetheretherketone (PEEK) is fixed on the sample stage of the plasma immersion ion implantation device and brought into contact with the high-voltage electrode of the device. Then, a vacuum is drawn to a vacuum level of 2 × 10⁻⁶. -3 The vacuum was maintained at 10 min. Then, nitrogen gas with a purity of 99.999 vol% was introduced. Next, the high-voltage pulse power supply was turned on, and the patterned polyether ether ketone was activated under the following parameters to obtain activated polyether ether ketone: implantation voltage of -20 kV, RF power of 200 W, pulse width of 30 μs, pulse frequency of 50 Hz, and ion implantation time of 20 min.

[0082] (3) Preparation of bioactive solution: Dissolve 5g of poly-L-lactic acid in 100mL of dichloromethane to obtain poly-L-lactic acid solution. Then, add 20g of 45S5 bioactive glass powder to the L-lactic acid solution and stir at 500rpm for 1h. Then, ultrasonically disperse at 600W for 10min to obtain bioactive solution.

[0083] The activated polyetheretherketone (PEEK) was immersed in a bioactive solution for 20 seconds, then pulled out at a speed of 5 mm / min and allowed to air dry until no more dripping, completing one dip-coating step. This process was repeated twice to obtain the surface-modified PEEK material. The surface-modified PEEK material was then placed in an oven and dried at 60°C for 12 hours.

[0084] Example 2 The only difference from Example 1 is that polyglycolic acid is used instead of polylactic acid when preparing the bioactive solution.

[0085] Example 3 The only difference from Example 1 is that poly(lactic acid) is used instead of poly(L-lactic acid) when preparing the bioactive solution.

[0086] Comparative Example 1 The only difference from Example 1 is that 45S5 bioactive glass powder is not added when preparing the bioactive solution.

[0087] Comparative Example 2 The only difference from Example 2 is that 45S5 bioactive glass powder is not added when preparing the bioactive solution.

[0088] Comparative Example 3 The only difference from Example 3 is that 45S5 bioactive glass powder is not added when preparing the bioactive solution.

[0089] Comparative Example 4 The only difference from Example 2 is that plasma immersion ion implantation is not performed; the patterned polyether ether ketone is directly dipped into the bioactive solution.

[0090] Comparative Example 5 The only difference from Example 2 is that the femtosecond laser treatment is not performed; instead, the dried PEEK sample is directly subjected to plasma immersion ion implantation.

[0091] Experimental Example 1 The surface of the patterned polyetheretherketone prepared in Example 1 was observed under a microscope, and the results are as follows: Figure 3 As shown. By Figure 3 It is understood that the patterned polyetheretherketone of the present invention has regularly arranged regular square frustum-shaped protrusions on its surface.

[0092] Experimental Example 2 The minimum water contact angles of the dried PEEK samples, the surface-modified polyetheretherketone materials prepared in Examples 1-3, and Comparative Examples 1-3 were measured respectively, and the results are as follows: Figure 4 As shown.

[0093] Depend on Figure 4 It can be seen that the minimum water contact angles of the dried PEEK sample, the surface-modified polyetheretherketone materials prepared in Examples 1-3, and the surface-modified polyetheretherketone materials prepared in Comparative Examples 1-3 are 92°, 72°, 50°, 60°, 101°, 68°, and 82°, respectively. The surface-modified polyetheretherketone material of the present invention has a smaller minimum water contact angle and a better effect on improving bioinertness.

[0094] Experimental Example 3 The minimum water contact angles of the surface-modified polyetheretherketone (PEEK) materials prepared in Example 2 and Comparative Examples 4-5 were measured respectively. The three groups of surface-modified PEEK materials were then placed at room temperature (25°C) for 4 weeks, and the water contact angles of the surface-modified PEEK materials were measured again. The results are as follows: Figure 5 As shown.

[0095] Depend on Figure 5 It can be seen that the surface-modified polyetheretherketone (PEEK) materials prepared in Comparative Examples 4 and 5 showed a significant increase in water contact angle after 4 weeks of storage, indicating a significant increase in bioinertness and a marked decrease in the stability of the surface modification. In contrast, the surface-modified PEEK material prepared in Example 2 showed no significant increase in water contact angle after 4 weeks of storage, maintained a longer minimum water contact angle, exhibited lower bioinertness, and demonstrated higher stability of the surface modification.

[0096] Experiment Example 4 The dried PEEK samples and the surface-modified polyetheretherketone materials prepared in Examples 1-3 were washed sequentially with 75 vol% ethanol aqueous solution and 0.01 M PBS solution, repeated three times (including the first wash). 250 μL of DMEM medium containing 10% fetal bovine serum (FBS) was added to each well of a 48-well plate (12.5 mm pore size). The washed polyetheretherketone materials were then placed in the medium. The groups were as follows: Experimental group: Mouse fibroblasts NIH3T3 (from the Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences) were seeded in a culture medium containing polyetheretherketone (PEEK). Control group: Mouse fibroblasts NIH3T3 were directly seeded in blank culture medium. Blank group: Blank culture medium without cells. Each group was set up in 3 replicates and cultured at 37°C and 5 vol% CO2 for different times (24 h, 48 h, 72 h). Then, serum-free culture medium was used to replace the original culture medium, followed by the addition of 10 vol% CCK-8 culture medium, and cultured for another 1 h. Then, the absorbance at a wavelength of 450 nm was measured using an ELISA reader, and the cell viability was calculated using the following formula (1): (1) Where As is the absorbance of the experimental group, Ab is the absorbance of the control group, and Ac is the absorbance of the blank group.

[0097] Cell survival rate, such as Figure 6 As shown.

[0098] Depend on Figure 6 As can be seen, compared with the PEEK sample, the cell survival rate of the surface-modified polyetheretherketone (PEEK) materials prepared in Examples 1-3 was significantly improved, with an overall cell survival rate exceeding 90%. The surface-modified PEEK material of this invention is non-cytotoxic and exhibits good biocompatibility.

[0099] This invention is not limited to the above-described embodiments. Any modifications, improvements, or substitutions that can be conceived by those skilled in the art without departing from the essential content of this invention fall within the scope of this invention.

Claims

1. A method for preparing a surface-modified polyetheretherketone (PEEK) material, characterized in that, Includes the following steps: 1) Patterned polyetheretherketone (PEEK) is obtained by etching regularly arranged protrusions on its surface using a femtosecond laser; wherein the protrusions are in the shape of a regular frustum. 2) The patterned polyether ether ketone surface is activated under vacuum conditions by nitrogen-sourced plasma immersion ion implantation to obtain activated polyether ether ketone; 3) The surface of activated polyetheretherketone is coated with a bioactive solution to obtain a surface-modified polyetheretherketone material; wherein, the solute of the bioactive solution is a biodegradable polyester and a bioactive substance; the biodegradable polyester is selected from at least one of poly(L-lactic acid), polyglycolic acid, polyglycolic acid, polycaprolactone, and polyhydroxyalkanoates, and the bioactive substance is selected from at least one of bioactive glass, calcium phosphate-based bioceramics, and hydroxyapatite; in the bioactive solution, based on 100 mL of solvent, the amount of biodegradable polyester is 1-20 g, and the amount of bioactive substance is 5-50 g.

2. The preparation method according to claim 1, characterized in that, In step 1), the protrusion is a regular square frustum, with the upper base side length being 5-50 μm, the lower base side length being 20-100 μm, and the height being 5-50 μm; The distance between two adjacent protrusions is 10 to 100 μm.

3. The preparation method according to claim 1, characterized in that, In step 1), the control parameters of the femtosecond laser are as follows: The linearly polarized light has a center wavelength of 200–500 nm, a spot diameter of 5–30 μm, a spot overlap rate of 30–95%, a pulse width of 50–200 fs, and an output power of 20–80 mW; the scanning speed is 5–50 mm / s, the scanning interval is 20–50 μm, and the number of scans is 2–8.

4. The preparation method according to claim 1, characterized in that, In step 2), the vacuum degree of the vacuum condition is 0.5 × 10⁻⁶. -3 ~5×10 -3 Pa.

5. The preparation method according to claim 1, characterized in that, In step 2), the control parameters for the nitrogen source plasma immersion ion implantation are as follows: The implantation voltage is -5 to -50 kV, the radio frequency power is 100 to 300 W, the pulse width is 5 to 60 μs, the pulse frequency is 20 to 100 Hz, and the ion implantation time is 10 to 60 min.

6. The preparation method according to claim 1, characterized in that, In step 3), the coating is dip coating.

7. The preparation method according to claim 6, characterized in that, In step 3), the number of dip coatings is 1 to 5 times; wherein the soaking time for each dip coating is 10 to 60 seconds, and the pull-out speed for each dip coating is 1 to 10 mm / min.

8. The preparation method according to claim 1, characterized in that, In step 3), the solvent is selected from at least one of dichloromethane, hexafluoroisopropanol, N-methylpyrrolidone, tetrahydrofuran, dimethylformamide, dimethyl sulfoxide, and trifluoroethanol.

9. A surface-modified polyetheretherketone material prepared by the preparation method according to any one of claims 1 to 8, characterized in that, The minimum water contact angle of the surface-modified polyetheretherketone material is less than or equal to 78°, and the minimum water contact angle is maintained for at least 25 days.

10. Use of the surface-modified polyetheretherketone material according to claim 9 in the preparation of orthopedic implants.

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