Degradable polylactic acid-based human cell sampling brush wire material and preparation method thereof
By modifying the preparation method of polylactic acid-based materials, the problems of breakage and thermal deformation of polylactic acid-based cell sampling brush filaments were solved, improving mechanical properties and heat resistance, reducing breakage risk, broadening the processing window and shortening degradation time.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-31
- Publication Date
- 2026-03-27
AI Technical Summary
Polylactic acid-based cell sampling brush bristles are prone to breakage under uneven stress or friction, and have a low heat distortion temperature, leading to tool failure or secondary damage risks.
By mixing polylactic acid with maleic anhydride and PBAT, adding epoxidized soybean oil and CaCO3, and then subjecting the mixture to ultraviolet treatment, a composite modified material was prepared. Combined with polyethylene glycol, plasticizer, and antibacterial agent, a biodegradable polylactic acid-based human cell sampling brush material was prepared.
It improves the mechanical properties and heat resistance of the bristle material, reduces the risk of breakage, widens the processing window, shortens the degradation time, and reduces the risk of cross-contamination.
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Figure CN121731561A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of medical product preparation technology, specifically to a biodegradable polylactic acid-based human cell sampling brush material and its preparation method. Background Technology
[0002] Polylactic acid (PLA) has become a mainstream biomedical material due to its high stability and excellent biocompatibility, as it does not rely on heavy metals or toxic additives. Its superior properties also meet the requirements of cell sampling brushes. However, PLA has relatively weak tensile strength and toughness, with an elongation at break typically below 10%. Therefore, sampling brushes made of pure PLA are prone to breakage during sampling due to uneven stress or friction. For example, during cervical sampling, the brush bristles must withstand bending and shearing forces, making them susceptible to breakage. Brittle material may remain in the patient's body, posing a risk of secondary injury. Furthermore, its heat distortion temperature is typically below 60°C, making it prone to deformation during high-temperature steam sterilization, leading to tool failure. Summary of the Invention
[0003] To address the shortcomings of existing technologies, this invention provides a biodegradable polylactic acid-based human cell sampling brush material and its preparation method, which can effectively improve the mechanical properties and heat resistance of the prepared cell extraction brush material.
[0004] To achieve the above objectives, the present invention provides the following technical solution: A biodegradable polylactic acid-based human cell sampling brush material, wherein the brush material is composed of the following raw materials in parts by weight: 75-90 parts of composite modified material, 4-6 parts of polyethylene glycol, 2-5 parts of plasticizer, and 0.5-0.7 parts of antibacterial agent; The composite modified material is obtained by mixing product A prepared from polylactic acid and maleic anhydride and product B prepared from polylactic acid and PBAT, followed by ultraviolet treatment.
[0005] Preferably, the plasticizer is one of tributyl acetylcitrate and the antibacterial agent is chlorhexidine.
[0006] Preferably, the specific preparation steps of the composite modified material are as follows: S1-1. Polylactic acid and maleic anhydride are fused to obtain product A; S1-2. Add polylactic acid and PBAT particles at a mass ratio of 5-7:4, dry, and premix for 5-10 min to obtain product B. S1-3. Add product A and product B at a mass ratio of 1:2-4, along with epoxidized soybean oil and CaCO3. Stir and irradiate with ultraviolet light for 10-20 minutes to obtain the composite modified material.
[0007] Preferably, the specific preparation steps of product A in step S1-1 are as follows: mixing polylactic acid and lactate peroxide for 6-8 min, adding maleic anhydride, mixing at 170-190℃ and 50-60 r / min for 5-10 min, cooling, pulverizing, and passing through a 60 mesh sieve. The mass ratio of polylactic acid, maleic anhydride, and lactate peroxide is 100:8:1.
[0008] Preferably, the mass ratio of product B, epoxidized soybean oil, and CaCO3 in steps S1-3 is 30:0.1-0.2:0.3.
[0009] Preferably, the wavelength of the ultraviolet light in steps S1-3 is 320-400 nm, and the radiation dose is 10-20 J / cm. 2 .
[0010] The specific steps of a method for preparing a biodegradable polylactic acid-based human cell sampling brush bristle material are as follows: S2-1. Add polyethylene glycol, plasticizer, and antibacterial agent to the composite modified material, mix, and obtain the treated material; S2-2. The processed material is put into an extruder and extruded, then cooled to room temperature to obtain the brush bristle material.
[0011] Preferably, the mixing speed in step S2-1 is 600-800 rpm.
[0012] Preferably, the extrusion temperature in step S2-2 is 170-190℃, and the diameter of the bristle material is 1-1.5mm.
[0013] This invention provides a biodegradable polylactic acid-based human cell sampling brush material and its preparation method, which has the following advantages compared with the prior art: This invention improves the mechanical properties of the prepared cell extraction brush material without affecting the existing characteristics of polylactic acid, especially its elastic recovery rate, giving it better elasticity and structural stability. This ensures that it maintains structural stability and operability when sampling from locations such as the cervix, thus comprehensively enhancing its application value as a cell extraction tool.
[0014] This solution improves the heat resistance of the finished brush bristle material, expands the processing window of the material, reduces the risk of thermal degradation, and also provides possibilities for high-temperature sterilization and other operations during use.
[0015] This solution can improve the degradation efficiency of brush bristle materials, that is, shorten their degradation time. On the one hand, it reduces the time occupied by their accumulation on land, and on the other hand, it reduces the risk of cross-infection due to incomplete disinfection or residue caused by excessive accumulation time. Attached Figure Description
[0016] Figure 1 The mechanical property test results for each prepared sample; Figure 2 The results of thermal stability tests for each prepared sample; Figure 3 The degradation rate test results are for each prepared sample. Detailed Implementation
[0017] The CaCO3 used had a particle size of 50-60 nm; polylactic acid was purchased from Haizheng Biotechnology; polyethylene glycol 600, used in this application, was purchased from Shanghai Yubo; maleic anhydride was purchased from Huifeng Petrochemical; epoxidized soybean oil was purchased from Qilu Petrochemical; lactate peroxide was purchased from Shanghai Huzheng Biotechnology's HZM9156; and poly(butylene adipate / terephthalate) (PBAT) was purchased from Lanshan Tunhe Co., Ltd.'s TH801T.
[0018] Preparation of composite modified materials: Composite modified material A: S1. Mix polylactic acid and lactate peroxide for 7 min, add maleic anhydride, and mix at 180℃ and 55 r / min for 8 min. The mass ratio of polylactic acid, maleic anhydride and lactate peroxide is 100:8:1. Cool, pulverize, and pass through a 60-mesh sieve to obtain product A. S2. Add polylactic acid and PBAT particles at a mass ratio of 6:4, dry, and premix for 8 min to obtain product B. S3. Add product A and product B at a mass ratio of 1:3, along with epoxidized soybean oil and CaCO3. The mass ratio of product B, epoxidized soybean oil, and CaCO3 is 20:0.15:0.3. While stirring, irradiate with ultraviolet light at a wavelength of 365nm for 15 minutes, with a radiation dose of 15J / cm. 2 Composite modified material A was obtained.
[0019] Composite modified material B: The preparation method of composite modified material B is the same as that of composite modified material A, except that S3 is adjusted, specifically as follows: S3. Add product A and product B at a mass ratio of 1:1, along with epoxidized soybean oil and CaCO3. The mass ratio of product B, epoxidized soybean oil, and CaCO3 is 20:0.15:0.3. While stirring, irradiate with ultraviolet light at a wavelength of 365nm for 15 minutes, with a radiation dose of 15J / cm². 2 Composite modified material B was obtained.
[0020] Composite modified material C: The preparation method of composite modified material C is the same as that of composite modified material A, except that S3 is adjusted. The other steps are the same, specifically: S3. Add product A and product B at a mass ratio of 1:5, along with epoxidized soybean oil and CaCO3. The mass ratio of product A, epoxidized soybean oil, and CaCO3 is 10:0.15:0.3. While stirring, irradiate with ultraviolet light at a wavelength of 365nm for 15 minutes, with a radiation dose of 15J / cm. 2 Thus, composite modified material C was obtained.
[0021] Composite modified material D: The preparation method of composite modified material D is the same as that of composite modified material A, except that steps S2 and S3 are adjusted, and the remaining steps are the same. Specifically: S2. Add product A and PBAT granules at a mass ratio of 6:4, dry, and premix for 8 min to obtain product B. S3. Add product B to epoxidized soybean oil and CaCO3, with a mass ratio of product B: epoxidized soybean oil: CaCO3 of 20:0.15:0.3. While stirring, irradiate with ultraviolet light at a wavelength of 365nm for 15 minutes, with a radiation dose of 15J / cm. 2 Thus, composite modified material D was obtained.
[0022] Composite modified material E: The preparation method of composite modified material E is the same as that of composite modified material A, except that S3 is adjusted. The other steps are the same, specifically: S3. Add product B to epoxidized soybean oil and CaCO3. The mass ratio of product B, epoxidized soybean oil and CaCO3 is 20:0.15:0.3. Stir to obtain composite modified material E.
[0023] Composite modified material F: The preparation method of composite modified material F is the same as that of composite modified material A, except that S3 is adjusted. The other steps are the same, specifically: S3. Add product B to epoxidized soybean oil and CaCO3. The mass ratio of product B, epoxidized soybean oil, and CaCO3 is 20:0.15:0.3. While stirring, irradiate with ultraviolet light at a wavelength of 365nm for 15 minutes, with a radiation dose of 25J / cm. 2 The composite modified material F was obtained.
[0024] Composite modified material G: S1. Add polylactic acid and PBAT particles at a mass ratio of 6:4, dry, and premix for 8 min to obtain product B. S2 adds epoxidized soybean oil and CaCO3 to product B, with a mass ratio of product B, epoxidized soybean oil, and CaCO3 of 20:0.15:0.3. While stirring, the mixture is irradiated with ultraviolet light at a wavelength of 365 nm for 15 minutes, with a radiation dose of 15 J / cm². 2 Thus, the composite modified material G was obtained.
[0025] Example 1: A method for preparing a biodegradable polylactic acid-based human cell sampling brush bristle material includes the following steps: S1. Weigh out 75 parts of composite modified material A, 6 parts of polyethylene glycol, 2 parts of tributyl acetylacetic acid, and 0.5 parts of chlorhexidine. S2. Add polyethylene glycol, tributyl acetyl citrate, and chlorhexidine to composite modified material A, and mix at 700 rpm to obtain the treated material. S3. The processed material is put into an extruder and extruded at an extrusion temperature of 180℃. The diameter of the bristle material is 1.3mm. After cooling to room temperature, the bristle material is obtained.
[0026] Example 2: This embodiment refers to the preparation method of Example 1, only the proportion of each material is different, and all other steps are the same, specifically: S1. Weigh out 90 parts of composite modified material A, 4 parts of polyethylene glycol, 5 parts of tributyl acetyl citrate, and 0.7 parts of chlorhexidine; Comparative example: This comparative example follows the preparation method of Example 1, with 7 experimental groups set up, and the specific selection of composite modifying materials is changed, as shown in Table 1: Table 1 Detection: 1. Safety testing: 1.1 In vivo experiments Medical-grade silicone was used as a blank control group. Eighteen male and eighteen female C57BL / 6 mice, aged 6 weeks, were randomly divided into 6 groups, with 3 males and 3 females in each group. On the same day, the hair on the backs of the mice was removed, and a 2cm piece of brush-like material was implanted on one side, while medical-grade silicone was implanted on the other side. The mice were then fed routinely and observed for 24 hours. The implants and surrounding tissues were then removed for tissue observation, and the results were all satisfactory.
[0027] 1.2 In vitro experiments A blank control group without brush bristle material was set up. Brush bristle material was prepared according to the methods in Examples 1-2 and Experimental Groups 1-7. The sterilized 2cm brush bristle material sample was directly placed into a cell culture plate and inoculated with human cervical epithelial cells (density approximately 1×10⁶). 4 The brush material was placed in the cell culture plate for 5 seconds and 15 seconds, and then removed. The cell viability was detected by the CCK-8 assay. The results are shown in Table 2 below. Table 2 As shown in the table above, the brush filament materials prepared according to the methods of Examples 1-2 and Experimental Groups 1-7 have no effect on cell viability.
[0028] 2. Mechanical performance testing The properties of the brush bristle materials prepared in Examples 1-2 and Experimental Groups 1-7 were tested. Tensile strength was measured according to standard GB / T1040.1-2018, using a universal testing machine to determine tensile strength, elongation at break, and elastic recovery. The contact angle of polylactic acid with water was measured using a contact angle meter to characterize the hydrophilicity of the material. The test results are shown in Table 3. Figure 1 As shown: Table 3 As shown in the table above, the brush bristle materials prepared in Examples 1 and 2 performed well in the tested items. Based on the comparative examples, experimental groups 4 and 7 were observed. Although the elongation at break of experimental group 4 was higher than that of experimental group 1, its tensile strength remained at a low level. While the tensile strength of experimental group 7 increased, its elastic recovery rate was poor. Experimental group 5 had a better elongation at break, but its contact corner cell sampling operation was too large, which did not meet the actual needs. Overall, Example 1 showed the best results.
[0029] 3. Thermal stability test The heat resistance temperature test method is as follows: A small segment of brush bristle material with a length of 30±0.2 mm was prepared. The test sample was heated from room temperature to 400℃ at a heating rate of 10℃ / min under a nitrogen atmosphere. After 3 minutes, the sample was removed and dried with absorbent paper. The temperature at which the small segment of brush bristle material just began to deform was taken as the heat resistance temperature. After cooling to room temperature, the tensile strength, elongation at break, and elastic recovery rate were tested. Specific results are shown in Table 4 and... Figure 2 As shown: Table 4 As shown in the table above, Example 1 exhibited the best heat resistance performance in the heat resistance test, with a heat resistance temperature exceeding both the normal operating temperature and the extrusion temperature, preventing performance loss immediately after extrusion. Observing the experimental group data, both Experimental Groups 5 and 6 adjusted the UV treatment steps during the preparation of the finished brush bristle material. The heat resistance temperatures of both Experimental Groups 5 and 6 decreased significantly. Although Experimental Group 6 had a higher radiation dose than Example 1 and a higher heat resistance temperature than the extrusion temperature, its tensile strength and elongation at break after heat treatment decreased significantly, drastically reducing its practicality.
[0030] 4. Degradation rate test Composting degradation rate: The degradation rate of the samples was assessed according to the method for determining the released carbon dioxide in the national standard GB / T 19277.1-2011 "Determination of the final aerobic biodegradability of materials under controlled composting conditions using the method of determining the released carbon dioxide". Once the samples had completely degraded, further observation was discontinued. Specific results are shown in Table 5 and... Figure 3 As shown: Table 5 As shown in the table above, Example 1 completed all degradation within 30 days, and by day 7, it had already achieved 85.12% degradation, indicating relatively rapid degradation. Observing the experimental group data, Experimental Group 2 showed rapid degradation from days 7 to 15, but not complete degradation. From days 15 to 90, its degradation rate increased slowly from 89.62% to 100%, resulting in a longer degradation time. While the degradation rate of Experimental Group 3 increased from 70.86% to 100% from days 30 to 90, its increase from 63.56% to 70.86% from days 7 to 30 was very slow, also contributing to a prolonged degradation time. Adding product A and product B at a 1:3 mass ratio positively impacted the degradation rate. Although the growth rate of Experimental Group 4 was stable, its degradation rate was relatively low in the initial 7 days. In summary, Example 1 performed better in the degradation rate test.
[0031] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0032] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.
Claims
1. A biodegradable polylactic acid-based human cell sampling brush material, characterized in that, The bristle material is composed of the following raw materials in parts by weight: 75-90 parts of composite modified material, 4-6 parts of polyethylene glycol, 2-5 parts of plasticizer, and 0.5-0.7 parts of antibacterial agent; The composite modified material is obtained by mixing product A prepared from polylactic acid and maleic anhydride and product B prepared from polylactic acid and PBAT, followed by ultraviolet treatment.
2. The bristle material according to claim 1, characterized in that, The plasticizer is tributyl acetylcitrate, and the antibacterial agent is chlorhexidine.
3. The bristle material according to claim 1, characterized in that, The specific preparation steps of the composite modified material are as follows: S1-1. Polylactic acid and maleic anhydride are fused to obtain product A; S1-2. Add polylactic acid and PBAT particles at a mass ratio of 5-7:4, dry, and premix for 5-10 min to obtain product B. S1-3. Add product A and product B at a mass ratio of 1:2-4, along with epoxidized soybean oil and CaCO3. Stir and irradiate with ultraviolet light for 10-20 minutes to obtain the composite modified material.
4. The bristle material according to claim 3, characterized in that, The specific preparation method of product A in step S1-1 is to mix polylactic acid and lactate peroxide for 6-8 min, add maleic anhydride, mix at 170-190℃ and 50-60 r / min for 5-10 min, cool, pulverize, and pass through a 60 mesh sieve. The mass ratio of polylactic acid, maleic anhydride, and lactate peroxide is 100:8:
1.
5. The bristle material according to claim 3, characterized in that, In steps S1-3, the mass ratio of product B, epoxidized soybean oil, and CaCO3 is 30:0.1-0.2:0.
3.
6. The bristle material according to claim 3, characterized in that, In steps S1-3, the wavelength of the ultraviolet light is 320-400 nm, and the radiation dose is 10-20 J / cm. 2 .
7. A method for preparing a biodegradable polylactic acid-based human cell sampling brush bristle material as described in any one of claims 1-6, characterized in that, The specific preparation steps are as follows: S2-1. Add polyethylene glycol, plasticizer, and antibacterial agent to the composite modified material, mix, and obtain the treated material; S2-2. The processed material is put into an extruder and extruded, then cooled to room temperature to obtain the brush bristle material.
8. The preparation method according to claim 7, characterized in that, The mixing speed in step S2-1 is 600-800 rpm.
9. The preparation method according to claim 7, characterized in that, The extrusion temperature in step S2-2 is 170-190℃, and the diameter of the bristle material is 1-1.5mm.