A method for preparing a hydrophilic antibacterial medical catheter

Abstract

The present invention relates to the field of medical devices, and in particular to a method for preparing a hydrophilic antibacterial medical catheter. The present invention first prepares an acrylamide type quaternary ammonium salt with antibacterial properties, then grafts 1,4-butanediol glycidyl ether with a hydrophilic segment to obtain hydrophilicity, and then reacts with chitosan to enhance the antibacterial property to obtain a hydrophilic antibacterial coating, and the coating is applied to the surface of the catheter to obtain a medical catheter with hydrophilic antibacterial properties. The coating has good firmness, can reduce infection, and can also reduce friction between the catheter and tissue, thereby alleviating the pain of patients.

Description

Technical Field

[0001] The invention relates to the field of medical devices, and in particular to a method for preparing a hydrophilic antibacterial medical catheter. Background Art

[0002] Medical catheters are widely used in clinical practice to deliver drugs, drain fluids, introduce instruments, come into contact with human cavities, damaged surfaces or blood, and are retained in the human body for a short or long period of time. However, the friction resistance formed during use can easily cause damage to blood vessels and cavity tissues, which in turn can cause other inflammations and increase the patient's pain; and bacteria can easily adhere to the catheter during entry or retention, causing infection. It is known that 60% to 70% of infections are related to medical devices, among which catheter-related urinary tract infections and catheter-related bloodstream infections are more common. Among nosocomial infections worldwide, urinary tract infections caused by catheters account for about 80%. In the United States alone, there are more than 1 million cases of infection, and the annual treatment cost exceeds US$350 million.

[0003] Patent CN117899273A discloses a method for preparing a lubricating antibacterial hydrogel coating that is firmly bonded to a catheter, in which a hydrogel coating is prepared on the surface of a polyvinyl chloride catheter by a surface initiated polymerization method. The material used in the invention has good biocompatibility, and the prepared medical catheter coating has good lubrication and antibacterial properties. In addition, the medical catheter coating prepared by free radical polymerization is firm and stable, and can extend the service life of the medical catheter.

[0004] Patent CN108992714A discloses a method for preparing a hydrophilic medical catheter. Raw materials such as PVC resin, natural latex, chitosan, lactic acid fiber, acetylsalicylic acid, and diethylene glycol dibenzoate are subjected to a heating reaction and a pressurized defoaming treatment, and then an activator component and an antibacterial agent component are fixed to the inner and outer wall surfaces of the catheter by means of an ultrasonic medium through a mold dipping method to obtain a hydrophilic medical catheter with good pressure resistance, tensile resistance, and hydrophilic properties.

[0005] Patent CN106110403A cross-links a high molecular polymer / monomer with a hydrophilic group with nano silver ions or chitin and a coating solution containing carbamate and siloxane, and then coats the cross-linked solution on the catheter surface to prepare a medical catheter with good hydrophilic and antibacterial properties.

[0006] In view of the lubrication requirements and antibacterial and anti-infection needs of medical catheters in clinical use, preparing a functional coating on the catheter surface that has both antibacterial and lubricious properties can reduce patient pain and reduce medical care costs. Summary of the invention

[0007] The present invention prepares a medical catheter with an antibacterial super-slip coating, and the specific invention content is as follows:

[0008] (1) 2-aminoethyl methacrylate hydrochloride was placed in a three-necked flask, and distilled water was added to dissolve it. The oil bath temperature was raised to 65-70°C under a N2 environment. N-isopropyl acrylamide was added to the three-necked flask, and then 0.02 g of initiator azobisisobutyronitrile was added. The reaction was continued for 4 h to 6 h. After cooling, the mixture was filtered and washed twice with purified water to obtain poly-2-aminoethyl methacrylate-N-isopropyl acrylamide, which was then dried under vacuum at 40°C for 12 h.

[0009] (2) Add poly (2-aminoethyl methacrylate-N-isopropylacrylamide) into a three-necked flask containing anhydrous acetone, pass nitrogen gas for protection, heat the oil bath to 60-65°C, add ethyl bromide and react for 72 hours. After the reaction is completed, cool and filter, wash with anhydrous acetone 2-3 times, and vacuum dry to obtain poly (2-aminoethyl methacrylate-N-isopropylacrylamide quaternary ammonium salt;

[0010] (3) Put poly (2-aminoethyl methacrylate)-N-isopropyl acrylamide quaternary ammonium salt and 1,4-butanediol glycidyl ether into a three-necked flask, add anhydrous acetone to dissolve, heat to 60-65°C, stir to react, cool and filter, wash twice with anhydrous acetone, and dry to obtain poly (2-aminoethyl methacrylate)-N-isopropyl acrylamide quaternary ammonium salt grafted with 1,4-butanediol glycidyl ether;

[0011] (4) Add 1,4-butanediol glycidyl ether grafted poly (2-aminoethyl methacrylate)-N-isopropylacrylamide quaternary ammonium salt to a three-necked flask and dissolve it in anhydrous acetone. Then, dissolve chitosan in isopropanol and pour it into the three-necked flask. Heat the water bath to 75°C-85°C. Stir and react for 6h-10h. Then, treat the catheter with plasma and dip it in the reaction solution for 2-3s. Then, dry it in an oven at 40°C-45°C to obtain a hydrophilic antibacterial coated catheter.

[0012] Furthermore, in step (1), the molar ratio of 2-aminoethyl methacrylate hydrochloride to N-isopropylacrylamide is 8:7 to 12:7;

[0013] Furthermore, the mass of azobisisobutyronitrile added in step (1) is 0.02wt%-0.08wt% of the total amount of 2-aminoethyl methacrylate hydrochloride and N-isopropylacrylamide;

[0014] Furthermore, in step (2), the molar ratio of the poly (2-aminoethyl methacrylate)-N-isopropylacrylamide to ethyl bromide is 2:3 to 1:1;

[0015] Furthermore, in step (3), the molar ratio of poly (2-aminoethyl methacrylate)-N-isopropylacrylamide quaternary ammonium salt to 1,4-butanediol glycidyl ether is 1:10;

[0016] Furthermore, the reaction time of step (3) is 48 h;

[0017] Furthermore, in step (4), the molar ratio of the poly (2-aminoethyl methacrylate)-N-isopropylacrylamide quaternary ammonium salt grafted with 1,4-butanediol glycidyl ether) to chitosan is 5:2 to 7:2;

[0018] Furthermore, in step (4), the catheter dipping time is 2-3 seconds, and the oven temperature is 40°C-45°C.

[0019] The invention has the advantages that an acrylamide type quaternary ammonium salt with antibacterial properties is prepared, 1,4-butanediol glycidyl ether with a hydrophilic chain segment is grafted to obtain hydrophilicity, and then reacts with chitosan to enhance the antibacterial property, and finally a hydrophilic antibacterial coating is obtained. After the coating is applied to the surface of a catheter, a medical catheter with hydrophilic antibacterial properties is obtained. The coating has good firmness, can reduce infection, and can also reduce friction between the catheter and tissue, thereby alleviating the pain of patients. DETAILED DESCRIPTION

[0020] Comparative Example 1

[0021] (1) Take 0.4 mol of 2-aminoethyl methacrylate hydrochloride in a three-necked flask, add distilled water to dissolve it, heat it to 70°C in an oil bath under a N2 environment, add 0.28 mol of N-isopropylacrylamide into the three-necked flask, and then add 0.05 g of initiator azobisisobutyronitrile. React for 5 h, treat the catheter with plasma, dip it in the reaction solution for 3 seconds, take it out, and dry it in an oven at 45°C to obtain a hydrophilic antibacterial coated catheter.

[0022] Comparative Example 2

[0023] (1) Take 0.4 mol of 2-aminoethyl methacrylate hydrochloride in a three-necked flask, add distilled water to dissolve it, heat it to 70°C in an oil bath under N2 environment, add 0.28 mol of N-isopropyl acrylamide into the three-necked flask, and then add 0.05 g of initiator azobisisobutyronitrile. React for 5 h, cool and filter, wash twice with purified water to obtain poly 2-aminoethyl methacrylate-N-isopropyl acrylamide, and dry it in a vacuum at 40°C for 12 h.

[0024] (2) Take 0.1 mol of poly (2-aminoethyl methacrylate-N-isopropylacrylamide) and add it into a three-necked flask containing anhydrous acetone. Pass nitrogen gas for protection, raise the oil bath temperature to 65°C, add 0.125 mol of ethyl bromide and react for 36 hours. After the catheter is plasma treated, dip it in the reaction solution for 3 seconds, take it out and dry it in an oven at 45°C to obtain a hydrophilic antibacterial coated catheter.

[0025] Comparative Example 3

[0026] (1) Take 0.4 mol of 2-aminoethyl methacrylate hydrochloride in a three-necked flask, add distilled water to dissolve it, heat it to 70°C in an oil bath under N2 environment, add 0.28 mol of N-isopropyl acrylamide into the three-necked flask, and then add 0.05 g of initiator azobisisobutyronitrile. React for 5 h, cool and filter, wash twice with purified water to obtain poly 2-aminoethyl methacrylate-N-isopropyl acrylamide, and dry it in a vacuum at 40°C for 12 h.

[0027] (2) Take 0.1 mol of poly (2-aminoethyl methacrylate-N-isopropylacrylamide) and add it into a three-necked flask containing anhydrous acetone. Pass nitrogen protection, heat the oil bath to 65°C, add 0.125 mol of ethyl bromide and react for 36 hours. After the reaction is completed, cool and filter, wash with anhydrous acetone for 3 times, and vacuum dry to obtain poly (2-aminoethyl methacrylate-N-isopropylacrylamide quaternary ammonium salt.

[0028] (3) 0.1 mol of poly (2-aminoethyl methacrylate)-N-isopropylacrylamide quaternary ammonium salt) and 0.01 mol of 1,4-butanediol glycidyl ether were placed in a three-necked flask, anhydrous acetone was added to dissolve, the temperature was raised to 65°C, and the reaction was stirred for 24 h. After the catheter was plasma treated, it was dipped in the reaction solution for 3 seconds and taken out, and dried in an oven at 45°C to obtain a hydrophilic antibacterial coated catheter.

[0029] Comparative Example 4

[0030] (1) Take 0.35 mol of 2-aminoethyl methacrylate hydrochloride in a three-necked flask, add distilled water to dissolve it, heat it to 70°C in an oil bath under a N2 environment, add 0.35 mol of N-isopropylacrylamide to the three-necked flask, and then add 0.01 g of initiator azobisisobutyronitrile. React for 5 h, cool and filter, wash twice with purified water to obtain poly (2-aminoethyl methacrylate-N-isopropylacrylamide), and dry it in a vacuum at 40°C for 12 h.

[0031] (2) Take 0.05 mol of poly (2-aminoethyl methacrylate-N-isopropylacrylamide) and add it into a three-necked flask containing anhydrous acetone. Pass nitrogen gas through it and heat the oil bath to 65°C. Add 0.15 mol of ethyl bromide and react for 48 hours. After the reaction is completed, cool and filter, wash with anhydrous acetone for 3 times, and vacuum dry to obtain poly (2-aminoethyl methacrylate-N-isopropylacrylamide quaternary ammonium salt.

[0032] (3) 0.05 mol of poly (2-aminoethyl methacrylate)-N-isopropylacrylamide quaternary ammonium salt and 0.01 mol of 1,4-butanediol glycidyl ether were placed in a three-necked flask, anhydrous acetone was added to dissolve, the temperature was raised to 65°C, and the mixture was stirred for reaction for 48 hours. After the reaction was completed, the mixture was cooled and filtered, washed twice with anhydrous acetone, and dried to obtain poly (2-aminoethyl methacrylate)-N-isopropylacrylamide quaternary ammonium salt grafted with 1,4-butanediol glycidyl ether.

[0033] (4) Add 0.003 mol of 1,4-butanediol glycidyl ether grafted poly (2-aminoethyl methacrylate)-N-isopropylacrylamide quaternary ammonium salt into a three-necked flask and dissolve it in anhydrous acetone. Then, take 0.002 mol of chitosan and dissolve it in isopropanol and pour it into the three-necked flask. Heat the mixture to 80 °C in a water bath and stir to react for 10 h. Then, treat the catheter with plasma, dip it in the reaction solution for 3 seconds, take it out, and dry it in an oven at 45 °C to obtain a hydrophilic antibacterial coated catheter.

[0034] Comparative Example 5

[0035] (1) Take 0.31 mol of 2-aminoethyl methacrylate hydrochloride in a three-necked flask, add distilled water to dissolve it, heat it to 70°C in an oil bath under a N2 environment, add 0.43 mol of N-isopropylacrylamide to the three-necked flask, and then add 0.04 g of initiator azobisisobutyronitrile. React for 5 h, cool and filter, wash twice with purified water to obtain poly (2-aminoethyl methacrylate-N-isopropylacrylamide), and dry it in a vacuum at 40°C for 12 h.

[0036] (2) Take 0.1 mol of poly (2-aminoethyl methacrylate-N-isopropylacrylamide) and add it into a three-necked flask containing anhydrous acetone. Pass nitrogen gas through it and heat the oil bath to 65°C. Add 0.05 mol of ethyl bromide and react for 72 hours. After the reaction is completed, cool and filter, wash with anhydrous acetone for 3 times, and vacuum dry to obtain poly (2-aminoethyl methacrylate-N-isopropylacrylamide quaternary ammonium salt.

[0037] (3) 0.1 mol of poly (2-aminoethyl methacrylate)-N-isopropylacrylamide quaternary ammonium salt and 0.01 mol of 1,4-butanediol glycidyl ether) were placed in a three-necked flask, anhydrous acetone was added to dissolve, the temperature was raised to 65°C, and the mixture was stirred for reaction for 48 hours. After the reaction was completed, the mixture was cooled and filtered, washed twice with anhydrous acetone, and dried to obtain poly (2-aminoethyl methacrylate)-N-isopropylacrylamide quaternary ammonium salt grafted with 1,4-butanediol glycidyl ether.

[0038] (4) Add 0.005 mol of 1,4-butanediol glycidyl ether grafted poly (2-aminoethyl methacrylate)-N-isopropylacrylamide quaternary ammonium salt into a three-necked flask and dissolve it in anhydrous acetone. Then, take 0.001 mol of chitosan and dissolve it in isopropanol and pour it into the three-necked flask. Heat the mixture to 80 °C in a water bath and stir to react for 10 h. Then, treat the catheter with plasma, dip it in the reaction solution for 3 seconds, take it out, and dry it in an oven at 45 °C to obtain a hydrophilic antibacterial coated catheter.

[0039] Example 1

[0040] (1) Take 0.39 mol of 2-aminoethyl methacrylate hydrochloride in a three-necked flask, add distilled water to dissolve it, heat it to 70°C in an oil bath under N2 environment, add 0.34 mol of N-isopropylacrylamide into the three-necked flask, and then add 0.02 g of initiator azobisisobutyronitrile. React for 5 h, cool and filter, wash twice with purified water to obtain poly (2-aminoethyl methacrylate-N-isopropylacrylamide), and dry it in vacuum at 40°C for 12 h.

[0041] (2) Take 0.1 mol of poly (2-aminoethyl methacrylate-N-isopropylacrylamide) and add it into a three-necked flask containing anhydrous acetone. Pass nitrogen gas through it and heat the oil bath to 65°C. Add 0.15 mol of ethyl bromide and react for 72 hours. After the reaction is completed, cool and filter, wash with anhydrous acetone for 3 times, and vacuum dry to obtain poly (2-aminoethyl methacrylate-N-isopropylacrylamide quaternary ammonium salt.

[0042] (3) 0.1 mol of poly (2-aminoethyl methacrylate)-N-isopropylacrylamide quaternary ammonium salt and 0.01 mol of 1,4-butanediol glycidyl ether) were placed in a three-necked flask, anhydrous acetone was added to dissolve, the temperature was raised to 65°C, and the mixture was stirred for reaction for 48 hours. After the reaction was completed, the mixture was cooled and filtered, washed twice with anhydrous acetone, and dried to obtain poly (2-aminoethyl methacrylate)-N-isopropylacrylamide quaternary ammonium salt grafted with 1,4-butanediol glycidyl ether.

[0043] (4) Add 0.005 mol of 1,4-butanediol glycidyl ether grafted poly (2-aminoethyl methacrylate)-N-isopropylacrylamide quaternary ammonium salt to a three-necked flask and dissolve it in anhydrous acetone. Then, take 0.002 mol of chitosan and dissolve it in isopropanol and pour it into the three-necked flask. Heat the mixture to 80 °C in a water bath and stir to react for 6 h. Then, treat the catheter with plasma, dip it in the reaction solution for 3 seconds, take it out, and dry it in an oven at 45 °C to obtain a hydrophilic antibacterial coated catheter.

[0044] Example 2

[0045] (1) Take 0.43 mol of 2-aminoethyl methacrylate hydrochloride in a three-necked flask, add distilled water to dissolve it, heat it to 70°C in an oil bath under a N2 environment, add 0.25 mol of N-isopropylacrylamide to the three-necked flask, the molar ratio of 2-aminoethyl methacrylate-N-isopropylacrylamide to ethyl bromide is 2:3, then add 0.08 g of initiator azobisisobutyronitrile, react for 5 h, cool and filter, wash twice with purified water to obtain poly 2-aminoethyl methacrylate-N-isopropylacrylamide, and dry it in a vacuum at 40°C for 12 h.

[0046] (2) Take 0.1 mol of poly (2-aminoethyl methacrylate-N-isopropylacrylamide) and add it into a three-necked flask containing anhydrous acetone. Pass nitrogen gas through it and heat the oil bath to 65°C. Add 0.1 mol of ethyl bromide and react for 72 hours. After the reaction is completed, cool and filter, wash with anhydrous acetone for 3 times, and vacuum dry to obtain poly (2-aminoethyl methacrylate-N-isopropylacrylamide quaternary ammonium salt.

[0047] (3) 0.1 mol of poly (2-aminoethyl methacrylate)-N-isopropylacrylamide quaternary ammonium salt and 0.01 mol of 1,4-butanediol glycidyl ether) were placed in a three-necked flask, anhydrous acetone was added to dissolve, the temperature was raised to 65°C, and the mixture was stirred for reaction for 48 hours. After the reaction was completed, the mixture was cooled and filtered, washed twice with anhydrous acetone, and dried to obtain poly (2-aminoethyl methacrylate)-N-isopropylacrylamide quaternary ammonium salt grafted with 1,4-butanediol glycidyl ether.

[0048] (4) Add 0.009 mol of 1,4-butanediol glycidyl ether grafted poly (2-aminoethyl methacrylate)-N-isopropylacrylamide quaternary ammonium salt and dissolve it in anhydrous acetone in a three-necked flask. Then, take 0.002 mol of chitosan and dissolve it in isopropanol and pour it into the three-necked flask. Heat the mixture to 80 °C in a water bath. Stir and react for 10 h. Then, treat the catheter with plasma, dip it in the reaction solution for 3 seconds, take it out, and dry it in an oven at 45 °C to obtain a hydrophilic antibacterial coated catheter.

[0049] Example 3

[0050] (1) Take 0.4 mol of 2-aminoethyl methacrylate hydrochloride in a three-necked flask, add distilled water to dissolve it, heat it to 70°C in an oil bath under N2 environment, add 0.28 mol of N-isopropyl acrylamide into the three-necked flask, and then add 0.05 g of initiator azobisisobutyronitrile. React for 5 h, cool and filter, wash twice with purified water to obtain poly 2-aminoethyl methacrylate-N-isopropyl acrylamide, and dry it in a vacuum at 40°C for 12 h.

[0051] (2) Take 0.1 mol of poly (2-aminoethyl methacrylate-N-isopropylacrylamide) and add it into a three-necked flask containing anhydrous acetone. Pass nitrogen protection, heat the oil bath to 65°C, add 0.125 mol of ethyl bromide and react for 36 hours. After the reaction is completed, cool and filter, wash with anhydrous acetone for 3 times, and vacuum dry to obtain poly (2-aminoethyl methacrylate-N-isopropylacrylamide quaternary ammonium salt.

[0052] (3) 0.1 mol of poly (2-aminoethyl methacrylate)-N-isopropylacrylamide quaternary ammonium salt and 0.01 mol of 1,4-butanediol glycidyl ether were placed in a three-necked flask, anhydrous acetone was added to dissolve, the temperature was raised to 65°C, and the mixture was stirred for reaction for 24 hours. After the reaction was completed, the mixture was cooled and filtered, washed twice with anhydrous acetone, and dried to obtain poly (2-aminoethyl methacrylate)-N-isopropylacrylamide quaternary ammonium salt grafted with 1,4-butanediol glycidyl ether.

[0053] (4) Add 0.008 mol of 1,4-butanediol glycidyl ether grafted poly (2-aminoethyl methacrylate)-N-isopropylacrylamide quaternary ammonium salt to a three-necked flask and dissolve it in anhydrous acetone. Then, take 0.002 mol of chitosan and dissolve it in isopropanol and pour it into the three-necked flask. Heat the mixture to 80 °C in a water bath and stir to react for 8 h. Then, treat the catheter with plasma, dip it in the reaction solution for 3 seconds, take it out, and dry it in an oven at 45 °C to obtain a hydrophilic antibacterial coated catheter.

[0054] Example 4

[0055] The uncoated silicone catheter and the hydrophilic antibacterial coated silicone catheters prepared in Example 1-3 and Comparative Example 1-2 were tested repeatedly 10 times using a friction tester. The friction coefficients are shown in Table 1.

[0056] Table 1

[0057] sample Uncoated Silicone Catheter Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Friction coefficient 2.8 0.07 0.06 0.04 2.12 2.15 1.02 1.61 1.44

[0058] As can be seen from the data in Table 1, the friction coefficient of the catheter prepared by the preparation method of the present invention is smaller than that of the uncoated catheter and the coated catheter, indicating that the coating is hydrophilic and can reduce the friction between the catheter and the tissue, and the friction coefficient is still very small after repeated friction for 10 times, proving that the coating and the catheter are firmly bonded. The friction coefficient of the coating prepared in the comparative example is significantly greater than that of the embodiment, proving the superiority of the preparation method of the present invention.

[0059] Example 5

[0060] Take the concentration as 10 6cfu / mL of Staphylococcus aureus was cultured in LB medium for 24 h. After dilution, a certain amount of the diluted sample was spread on a plate and cultured for 48 h. The number of bacteria on the surface of the uncoated silicone catheter and the hydrophilic antibacterial coated silicone catheter prepared in Example 1-3 and Comparative Example 1-2 was determined. The average values ​​of the three test results are shown in Table 2.

[0061] Table 2

[0062] sample Uncoated Silicone Catheter Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Bacterial count <![CDATA[5.1*10 9 ]]> <![CDATA[5.3*10 4 ]]> <![CDATA[3.6*10 4 ]]> <![CDATA[4.5*10 4 ]]> <![CDATA[4.7*10 9 ]]> <![CDATA[4.5*10 9 ]]> <![CDATA[1.2*10 6 ]]> <![CDATA[7.3*10 7 ]]> <![CDATA[9.4*10 6 ]]>

[0063] It can be seen from the data in Table 2 that the number of bacteria on the surface of the catheter prepared by the preparation method of the present invention is lower than the number of bacteria on the surface of the catheter prepared by the unmodified catheter and the comparative example, which proves that the preparation method of the present invention has better antibacterial performance.

Claims

1. A method for preparing a hydrophilic antibacterial medical catheter, characterized in that: The preparation method comprises: (1) 2-aminoethyl methacrylate hydrochloride was placed in a three-necked flask, and distilled water was added to dissolve it. The temperature of the oil bath was raised to 65-70° C. under a N2 environment. N-isopropyl acrylamide was added to the three-necked flask, and then an initiator azobisisobutyronitrile was added. The reaction was continued for 4 h to 6 h. After cooling, the mixture was filtered and washed twice with purified water to obtain poly-2-aminoethyl methacrylate-N-isopropyl acrylamide, which was vacuum dried at 40° C. for 12 h. (2) adding poly (2-aminoethyl methacrylate-N-isopropylacrylamide) into a three-necked flask containing anhydrous acetone, passing nitrogen gas for protection, heating the oil bath to 60-65° C., adding ethyl bromide, cooling and filtering after the reaction is completed, washing with anhydrous acetone 2-3 times, and vacuum drying to obtain poly (2-aminoethyl methacrylate-N-isopropylacrylamide quaternary ammonium salt; (3) putting poly (2-aminoethyl methacrylate-N-isopropyl acrylamide quaternary ammonium salt) and 1,4-butanediol glycidyl ether into a three-necked flask, adding anhydrous acetone to dissolve, heating to 60-65° C., stirring and reacting, cooling and filtering, washing twice with anhydrous acetone, and drying to obtain poly (2-aminoethyl methacrylate-N-isopropyl acrylamide quaternary ammonium salt grafted with 1,4-butanediol glycidyl ether); (4) Add 1,4-butanediol glycidyl ether grafted poly 2-aminoethyl methacrylate-N-isopropylacrylamide quaternary ammonium salt to a three-necked flask and dissolve it in anhydrous acetone, then take chitosan and dissolve it in isopropanol and pour it into the three-necked flask, heat it to 75°C-85°C in a water bath, stir and react for 6h-10h, dip the catheter into the reaction solution after plasma treatment for 2-3s, take it out, and dry it in an oven at 40°C-45°C to obtain a hydrophilic antibacterial coating catheter; The molar ratio of the 2-aminoethyl methacrylate hydrochloride to N-isopropyl acrylamide in step (1) is 8:7-12:7, and the mass of the added azobisisobutyronitrile is 0.02wt%-0.08wt% of the total amount of 2-aminoethyl methacrylate hydrochloride and N-isopropyl acrylamide; the molar ratio of the poly 2-aminoethyl methacrylate-N-isopropyl acrylamide to ethyl bromide in step (2) is 2:3-1:1; the molar ratio of the poly 2-aminoethyl methacrylate-N-isopropyl acrylamide quaternary ammonium salt to 1,4-butanediol glycidyl ether in step (3) is 1:10; and the molar ratio of the poly 2-aminoethyl methacrylate-N-isopropyl acrylamide quaternary ammonium salt grafted with 1,4-butanediol glycidyl ether to chitosan in step (4) is 5:2-7:

2.

2. A method for preparing a hydrophilic antibacterial medical catheter according to claim 1, characterized in that The reaction time of step (2) is 72h.

3. A method for preparing a hydrophilic antibacterial medical catheter according to claim 1, characterized in that The reaction time of step (3) is 48h.