CN116836087B

CN116836087B - Preparation method of medical consumable substrate surface functionalized coating

Info

Publication number: CN116836087B
Application number: CN202310810636.1A
Authority: CN
Inventors: 侯铮; 张鸿飞
Original assignee: Zhenghong Nova Medical Technology Shenzhen Co ltd
Current assignee: Zhenghong Nova Medical Technology Shenzhen Co ltd
Priority date: 2023-07-03
Filing date: 2023-07-03
Publication date: 2024-10-01
Anticipated expiration: 2043-07-03
Also published as: CN116836087A

Abstract

The invention relates to a preparation method of a medical consumable substrate surface functionalization coating, S1a, compound 3 and dopamine are prepared into a mixed solution 1 according to a proportion, the compound 3 is a compound with the following chemical formula,S1b, immersing the matrix in the mixed solution 1 to prepare a modified matrix; s1c, preparing a mixed solution 2 by using a crosslinkable cationic monomer and a crosslinking agent according to a proportion; s1d, soaking the modified substrate in the mixed solution 2 to prepare the coating on the surface of the substrate. The method utilizes the thermal initiator and the polydopamine field planting method to field-implant the initiator on the surface of the basal body of the medical consumable, and then initiates the cross-linkable cationic monomer and the cross-linking agent to carry out polymerization reaction by heating to form the firm cationic hydrophilic coating.

Description

Preparation method of medical consumable substrate surface functionalized coating

Technical Field

The invention relates to the field of surface coatings of medical equipment, in particular to a preparation method of a functional coating on the surface of a medical consumable substrate.

Background

Over the last decade, the overuse of antibiotics has prompted the growth of more and more resistant bacteria, and therefore the development of antibiotic replacement products is urgent. Cationic polymers have been the focus of research in the academic research and practical application of antibiotic replacement.

Since the cell membrane of bacteria is composed of negatively charged anionic fats, its structure can be broken down by the electrostatic action of cationic antibacterial agents, resulting in the lysis and death of bacteria. The sterilization of the cationic antibacterial agent mainly aims at the inherent biological characteristics of bacterial cell membranes, so that the cationic antibacterial agent has a broad-spectrum sterilization effect, and bacteria are extremely difficult to evolve effective drug resistance. Cationic antibacterial agents have broad prospects in the antibacterial field. The cationic polymer antibacterial agent is natural polymer such as polymer quaternary ammonium salt and its derivative, chitosan, dextran, etc. The cationic bactericidal coating has the advantages of low cost and broad spectrum. However, both cationic antimicrobial agents have their own drawbacks, such as the method of achieving cationic polymer coatings, mainly spraying, dipping, plating, etc. The polymer coating obtained by the process is easy to wash away by water or is directly stripped, the antibacterial performance is fast in failure, and a long-acting antibacterial coating is difficult to form. Meanwhile, because of the characteristic of positive charge, the coating can attract substances except bacteria, such as dust, protein and the like, slowly adhere or deposit on the surface of an object coated with the cationic polymer coating, and cover the charge of the cationic polymer, so that the antibacterial effect is lost. After the positive charges are covered, dirt such as dust, protein and the like gathers on the surface, and conditions and nutrients can be further provided for bacterial adhesion and capsular microorganism formation, so that bacteria can be more easily propagated. In view of this, the cationic polymer must form a crosslinked coating that is synergistic with the anti-fouling, protein-adhesive material to achieve a long-lasting antimicrobial effect.

The oxidation polymerization of dopamine can form a compact and firm coating on the surface of most substances such as silica gel, polyurethane, metal and ceramic. In the polymerization of dopamine, phenolic hydroxyl groups in molecules of the dopamine can be subjected to Schiff base reaction or Michael addition with organic amine groups so as to form firm covalent bonds with the dopamine coating, and the covalent bonds are co-implanted on the surface of the substance. Thus, the copolymerization of organic amines and dopamine is a common method of introducing functional molecules into the coating. However, the existing cationic antibacterial agent and the coating formed by the dopamine reaction solve the problem that the coating is easy to fall off, but the problem that the coating is easy to adhere to dust and protein to cause the loss of antibacterial performance is not solved.

Disclosure of Invention

Aiming at the defects in the prior art, the invention provides a preparation method of a functional coating on the surface of a medical consumable substrate.

The technical scheme adopted for solving the technical problems is as follows: a preparation method of a medical consumable substrate surface functionalization coating comprises the following steps:

S1a, dissolving a compound 3 and dopamine in a weak alkaline buffer solution in proportion to prepare a mixed solution 1; the concentration ratio of the compound 3 to the dopamine in the mixed solution 1 is 1-10mg/ml, and 0.5-5mg/ml; the compound 3 is a compound of the following chemical formula,

S1b, immersing a substrate in the mixed solution 1, standing for reaction to form a coating, and cleaning after the reaction is finished to obtain a modified substrate;

S1c, dissolving a crosslinkable cationic monomer and a crosslinking agent in water according to a proportion to prepare a mixed solution 2, and introducing nitrogen or inert gas to deoxidize the mixed solution 2; the concentration ratio of the crosslinkable cationic monomer to the crosslinking agent in the mixed solution 2 is 0.5-20g/ml and 0.05-2g/ml; the crosslinkable cationic monomer is any one of (3-acrylamide propyl) trimethyl ammonium chloride, 2- (methacryloyloxy) ethyl ] trimethyl ammonium chloride, diallyl dimethyl ammonium, [2- (acryloyloxy) ethyl ] trimethyl ammonium chloride; the crosslinking agent is a propylene crosslinking agent;

S1d, soaking the modified matrix in the mixed solution 2, reacting in a sealed reaction kettle at the temperature of 60-125 ℃, and cleaning after the reaction is finished to obtain the hydrophilic cationic polymer coating on the surface of the matrix.

Preferably, the weakly alkaline buffer solution is any one of phosphate buffer, tris (hydroxymethyl) aminomethane buffer, carbonate solution, and dilute ammonia water.

Preferably, the compound 3 is prepared by the steps of:

s3a, introducing an amino protecting group into ethanolamine to prepare a compound 1;

s3b, modifying 4,4' -azobis (4-cyanovaleric acid) with compound 1 to produce compound 2, said compound 1 having the formula: the compound 2 has the following chemical formula: wherein R is an amino protecting group;

S3c, dissolving the compound 2 in an organic solvent 5 to prepare a solution 4; slowly dripping trifluoroacetic acid into the solution 4 to react at room temperature in a dark place, concentrating the reacted solution after the reaction is completed, and precipitating the concentrated solution in diethyl ether to prepare a compound 3, wherein the organic solvent 5 is any one of dichloromethane, ethyl acetate, toluene, chloroform and tetrahydrofuran; the compound 3 is a compound of the following chemical formula,

Preferably, the amino protecting group is Boc, and the step S3a includes the steps of:

S3a-1, dissolving ethanolamine, di-tert-butyl dicarbonate and a catalyst 1 in an organic solvent 1 in proportion, reacting at room temperature, and performing reduced pressure spin drying after the reaction is finished to prepare a substance 1;

s3a-2, dissolving the substance 1 in a water-immiscible organic solvent 2 to form a solution 1;

S3a-3, sequentially extracting the solution 1 with sodium bicarbonate solution, citric acid solution, deionized water and saturated sodium chloride solution, separating an organic layer after extraction, drying the organic layer by adopting anhydrous magnesium sulfate or anhydrous sodium sulfate, and evaporating the organic layer under reduced pressure after drying to obtain a compound 1 introduced with Boc;

the step S3b includes the steps of:

s3b-1, directly adding 4,4' -azobis (4-cyano valeric acid) into the compound 1 and dissolving in an organic solvent 3 to prepare a solution 2;

s3b-2, adding a condensing agent and a catalyst 2 into the solution 2, and carrying out light-shielding reaction at room temperature under nitrogen or inert gas to prepare a solution 3;

S3b-3, spin-drying the solution 3, adding the solution into an organic solvent 4 which is not miscible with water for dissolution, sequentially extracting with sodium bicarbonate solution, citric acid solution, deionized water and saturated sodium chloride solution, separating out an organic layer after the extraction is finished, drying the organic layer by adopting anhydrous magnesium sulfate or anhydrous sodium sulfate, and evaporating the dried organic layer under reduced pressure to obtain the compound 2 with the introduced Boc.

Preferably, the organic solvent 1 is any one of tetrahydrofuran, dichloromethane, and ethyl acetate; the catalyst 1 is any one of triethylamine, trimethylamine, N-diisopropylethylamine and 4-dimethylaminopyridine; the organic solvent 2 is any one of ethyl acetate, toluene, methylene dichloride and chloroform; the organic solvent 3 is any one of tetrahydrofuran, dichloromethane, ethyl acetate and dimethylformamide; the catalyst 2 is any one of triethylamine, trimethylamine, N-diisopropylethylamine and 4-dimethylaminopyridine; the organic solvent 4 is any one of ethyl acetate, toluene, methylene dichloride and chloroform; the condensing agent is any one of ethyl carbodiimide hydrochloride, 1, 3-dicyclohexylcarbodiimide and N, N' -diisopropylcarbodiimide.

The invention has the beneficial effects that: the thermal initiator is prepared by modifying 4,4' -azobis (4-cyano valeric acid), then, the thermal initiator and polydopamine field planting method are utilized to field-planting the initiator on the surface of a basal body of medical consumable, a cross-linkable cationic polymer can realize a more stable and long-acting cationic antibacterial coating, and then, a cross-linkable cationic monomer and a cross-linking agent are heated to initiate polymerization reaction to form a firm cationic hydrophilic coating, so that a layer of compact water film with positive charges is formed, hydrophilic materials are introduced into the coating, and the anti-fouling and anti-protein adhesion effects of the cationic coating are improved. Thereby prolonging the antibacterial effect of the cationic coating, realizing the surface sterilization effect and improving the surface hydrophilicity of the matrix. Meanwhile, the preparation method is simple, a coating can be formed on the surface of the base material by a simple and easy soaking method, the polymerization/crosslinking process is high-temperature and high-pressure heating, the reaction rate is high, the production efficiency is high, the application range is wide, the method can be widely applied to the surface modification of medical equipment/consumables with different shapes such as metal, ceramic, silica gel and polyurethane, and the effects of inhibiting bacterial adhesion, capsular microorganism formation and infection are realized.

Drawings

FIG. 1 is a scanning electron microscope image of a cross section of a cationic hydrophilic coating according to an embodiment of the present invention;

FIG. 2 is a graph showing the change in hydrophilicity of Sylgard-184 silica gel according to an embodiment of the present invention after modification;

FIG. 3 is a comparison of contact sterilization performance of Sylgard-184 silica gel of the present invention after modification;

FIG. 4 is a comparison of antibacterial biofilm performance of the Sylgard-184 silica gel of the present invention after modification;

FIG. 5 is a schematic flow chart of the preparation of a surface coating of a medical consumable substrate according to an embodiment of the present invention;

Detailed Description

The present invention will be further described in connection with the following examples which are to be construed as illustrative and not limiting the scope of the invention. The implementation conditions used in the examples may be further adjusted according to the conditions of the specific manufacturer, and the implementation conditions not specified are generally those in routine experiments.

The embodiment of the invention relates to a thermal initiator and a synthesis method thereof, wherein the thermal initiator has the following chemical formula,

Wherein R is hydrogen or an amino protecting group; the amino protecting group is selected from Boc, fmoc, TFA, alloc, methoxycarbonyl and ethoxycarbonyl.

The synthesis steps are as follows:

The amino protecting group selected from Boc, steps as follows:

S3a-1, dissolving ethanolamine, di-tert-butyl dicarbonate and a catalyst 1 in an organic solvent 1 according to a proportion, dissolving the materials in a proportion of 0.8-1.5 mmol/ml of the organic solvent 1 to 1-1.5 mmol/ml of the organic solvent 1, reacting at room temperature for 18-20h, and performing reduced pressure spin drying after the reaction is finished to obtain a substance 1; the organic solvent 1 is any one of tetrahydrofuran, dichloromethane and ethyl acetate; the catalyst 1 is any one of triethylamine, trimethylamine, N-diisopropylethylamine and 4-dimethylaminopyridine,

S3a-2, dissolving the substance 1in a water-immiscible organic solvent 2 to form a solution 1; the organic solvent 2 is any one of ethyl acetate, toluene, methylene chloride and chloroform;

S3a-3, sequentially extracting the solution 1 with sodium bicarbonate solution, citric acid solution, deionized water and saturated sodium chloride solution, separating an organic layer by using a separating funnel after extraction, drying the separated organic layer by using anhydrous magnesium sulfate or anhydrous sodium sulfate, and evaporating under reduced pressure after drying to obtain a compound 1 with introduced Boc, wherein the compound 1 has the following chemical formula:

S3b, modifying 4,4' -azobis (4-cyano valeric acid) by using a compound 1 to obtain a compound 2, wherein the compound 2 has the following chemical formula:

The method comprises the following specific steps:

S3b-1, directly adding 4,4' -azobis (4-cyano valeric acid) into the compound 1 and dissolving in an organic solvent 3 to prepare a solution 2; the organic solvent 3 is any one of tetrahydrofuran, dichloromethane, ethyl acetate and dimethylformamide

S3b-2, adding a condensing agent and a catalyst 2 into the solution 2, and carrying out light-shielding reaction at room temperature under nitrogen or inert gas to prepare a solution 3; the catalyst 2 is any one of triethylamine, trimethylamine, N-diisopropylethylamine and 4-dimethylaminopyridine; the condensing agent is any one of ethyl carbodiimide hydrochloride, 1, 3-dicyclohexylcarbodiimide and N, N' -diisopropylcarbodiimide;

S3b-3, spin-drying the solution 3, adding the solution into an organic solvent 4 which is not miscible with water for dissolution, sequentially extracting with a sodium bicarbonate solution, a citric acid solution, deionized water and a saturated sodium chloride solution, separating an organic layer by using a separating funnel after the extraction is finished, drying the separated organic layer by using anhydrous magnesium sulfate or anhydrous sodium sulfate, and evaporating the dried organic layer under reduced pressure to obtain a compound 2 introduced with Boc; the organic solvent 4 is any one of ethyl acetate, toluene, methylene chloride and chloroform.

Further comprising a step S3c of dissolving compound 2 in an organic solvent 5 to prepare a solution 4; slowly dripping trifluoroacetic acid into the solution 4 to react at room temperature in a dark place, concentrating the reacted solution after the reaction is completed, and precipitating the concentrated solution in diethyl ether to prepare a compound 3, wherein the organic solvent 5 is any one of dichloromethane, ethyl acetate, toluene, chloroform and tetrahydrofuran; compound 3 is a compound of the formula,

Application of the thermal initiator in preparing the functional coating on the surface of the medical consumable substrate is shown in fig. 5, and the preparation method of the coating is as follows:

S1a, dissolving the prepared compound 3 and dopamine in a weakly alkaline buffer solution to prepare a mixed solution 1, wherein when R in the thermal initiator is an amino protecting group, the thermal initiator is treated in the step S3 and then R is changed into hydrogen, namely, the thermal initiator with the chemical formula of the compound 3 is adopted to react with the dopamine; the concentration ratio of the compound 3 to the dopamine in the mixed solution is 1-10mg/ml, 0.5-5mg/ml; the weak alkaline buffer solution is any one of phosphoric acid buffer solution, tris (hydroxymethyl) aminomethane buffer solution, carbonate solution and dilute ammonia water;

S1b, immersing a substrate in the mixed solution 1, standing for reaction to form a coating, carrying out cleaning after the reaction is completed for 4-6 hours to obtain a modified substrate, washing with deionized water, and washing for multiple times to clean residual free dopamine and compounds 3;

S1c, dissolving a crosslinkable cationic monomer and a crosslinking agent in water according to a proportion to prepare a mixed solution 2, introducing nitrogen or inert gas to deoxidize the mixed solution 2, introducing the nitrogen or the inert gas for 12-20min, and removing dissolved oxygen in the water through the introduced nitrogen or the inert gas; the concentration ratio of the crosslinkable cationic monomer to the crosslinking agent in the mixed solution 2 is 0.5-20g/ml and 0.05-2g/ml; the crosslinkable cationic monomer is a radically polymerizable monomer having a carbon-carbon double bond, such as acrylamide group-containing monomer (3-acrylamidopropyl) trimethylammonium chloride (AMPTMA), a methylpropenyl monomer such as 2- (methacryloyloxy) ethyl ] trimethylammonium chloride (MAETMA), an allylic monomer such as diallyldimethylammonium (DADMAC), and a propenyl monomer such as [2- (acryloyloxy) ethyl ] trimethylammonium chloride (AETMA); the crosslinking agent is propylene crosslinking agent, such as high molecular crosslinking agent such as dimethyl propylene polyethylene glycol, and small molecular crosslinking agent such as N, N' -methylene bisacrylamide;

S1d, soaking the modified matrix in the mixed solution 2, reacting at the temperature of 60-125 ℃ in a sealed reaction kettle for 20min-4h, and cleaning after the reaction is finished, the hydrophilic cationic polymer coating on the surface of the matrix is prepared by adopting shorter reaction time when the reaction temperature is higher, and cleaning residual hydrophilic crosslinkable cationic monomer, crosslinking agent and free polymer formed by self-polymerization of the monomer in the solution by deionized water, so that a layer of firmly-planted hydrophilic cationic polymer coating can be formed on the inner wall of the ultra-micro chamber.

Specific examples are as follows:

The synthetic route is as follows:

Preparation of Sylgard-184 silica gel sheet

The AB components of Sylgard-184 silica gel were mixed in the stated proportions (A: B=10:1) and poured into 10cm diameter petri dishes. Standing for 10 minutes, and waiting for bubbles visible to the naked eye to disappear. The petri dish with the silica gel was placed in a vacuum oven and evacuated to further expel the oxygen from the silica gel component. Thereby enabling the silica gel to be more thoroughly crosslinked. After 30 minutes of vacuum application, the oven was heated to 50 ℃ overnight to react to give a crosslinked Sylgard-184 silica gel sheet for modification and experimentation in the following steps.

Example 1

(1) Preparation of modified 4,4' -azobis (4-cyanovaleric acid) (ACVA-NH ₂), compound 3;

11.7 mmol of ethanolamine, 12 mmol of di-tert-butyl dicarbonate (Boc ₂ O) and 12 mmol of triethylamine are dissolved in 10 ml of tetrahydrofuran and reacted at room temperature for 18 hours, and then the solvent is dried under reduced pressure; redissolving the dried material in ethyl acetate and sequentially extracting with sodium bicarbonate solution, citric acid solution, deionized water and saturated sodium chloride solution; then, the organic layer was separated with a separating funnel and dried over anhydrous magnesium sulfate; the dried organic layer was evaporated to dryness under reduced pressure to give compound 1.

To compound 1, 0.93 mmol of 4,4' -azobis (4-cyanovaleric acid) (ACVA) was directly added and dissolved in 20 ml of Tetrahydrofuran (THF), and 2.0 mmol of 4- (dimethylamino) pyridine (DMAP) and 2.0 mmol of ethylcarbodiimide hydrochloride (EDC) were added and reacted at room temperature under nitrogen protection for 18 hours in the dark; spin-drying tetrahydrofuran, adding ethyl acetate again for dissolution, and sequentially extracting with sodium bicarbonate solution, citric acid solution, deionized water and saturated sodium chloride solution; the organic layer was then separated with a separating funnel and dried over anhydrous magnesium sulfate, and the dried organic layer was evaporated to dryness under reduced pressure to give Compound 2 having an amino protecting group of Boc.

0.15 Mmol of compound 2 with an amino protecting group of Boc is added into 20 ml of dichloromethane, 3 mmol of trifluoroacetic acid is slowly added dropwise, and the mixture is reacted for 12 hours at room temperature in the absence of light; the solution was then concentrated and the final modified ACVA was precipitated in diethyl ether and designated ACVA-NH ₂.

(2) Planting ACVA-NH ₂ on the surface of Sylgard-184 silica gel sheets;

2mg/mL of ACVA-NH ₂ and 1mg/mL of dopamine are mixed in proportion and dissolved in Tris buffer with pH of 8.5, a 1cm multiplied by 1cm square silica gel sheet is soaked in the solution, and the solution is allowed to stand for reaction for 4 hours. And then rinsed 3 times with deionized water to clean the remaining free dopamine and ACVA-NH ₂.

(3) Preparing a cationic hydrophilic coating by thermally initiating polymerization of hydrophilic monomers on the surface of the Sylgard-184 silica gel sheet;

1g (3-acrylamidopropyl) trimethylammonium chloride (AMPTMA) crosslinkable cationic monomer and 0.1g polyethylene glycol dimethacrylate (PEGDMA) crosslinker were dissolved in 10mL of water and 15 minutes of nitrogen was vented to remove dissolved oxygen from the water. Then, soaking a silica gel sheet with ACVA-NH ₂ planted on the surface in the solution, sealing and placing the silica gel sheet into a high-temperature high-pressure reaction kettle to react for 20 minutes at 120 ℃; after the polymerization reaction, washing hydrophilic monomer and cross-linking agent remained on the surface of silica gel with deionized water, and obtaining a modified sample of free polymer formed by self-polymerizing the monomer in the solution, which is marked as AMPTMA/PEGDMA coating.

Example 2: as in example 1, only the crosslinkable cationic monomer was replaced with a methacrylic monomer such as 2- (methacryloyloxy) ethyl ] trimethylammonium chloride (MAETMA), noted as MAETMA/PEGDMA coating.

Example 3: as in example 1, only the crosslinkable cationic monomer was replaced with diallyldimethylammonium (DADMAC), designated DADMAC/PEGDMA coating.

Example 4: as in example 1, except that the crosslinkable cationic monomer was replaced with [2- (acryloyloxy) ethyl ] trimethylammonium chloride (AETMA), designated AETMA/PEGDMA coating.

After various coatings were prepared, the coating characteristics were verified as follows

1) Culturing bacteria: staphylococcus aureus or escherichia coli was resuscitated in glycerol bacteria at-80 ℃ and cultured overnight, followed by 4 hours of secondary subculture. The cultured bacteria were centrifuged, washed 3 times with PBS buffer, and finally resuspended in PBS buffer to give a bacterial solution at a concentration of about 10 ⁸ CFU/mL.

2) And (3) verifying the contact sterilization effect of the antibacterial coating: uniformly coating 5 mu L of staphylococcus aureus bacterial liquid on the surface of a test material (such as polyurethane, silica gel, metal materials and the like), wherein the test material is the prepared Sylgard-184 silica gel sheet; wherein the negative control group was a Sylgard-184 silica gel matrix without any modification and the test group was a Sylgard-184 silica gel matrix with an antimicrobial coating (examples 1 to 4). After the test substrate coated with the bacterial liquid is cultured for 3 hours in an incubator at 37 ℃, the test substrate is soaked in a sterilized PBS buffer solution to wash out bacteria from the surface of the test substrate, and the bacteria are coated and counted.

3) Verification of the anti-biofilm effect: dispersing 5 mu L of bacterial liquid in 1mL of TSB culture liquid, soaking a silica gel material with a square of 5X5 mm in the TSB bacterial liquid, culturing and preserving overnight; wherein the negative control group is Sylgard-184 silica gel matrix without any modification, and the test group is Sylgard-184 silica gel matrix with antibacterial coating (examples 1 to 4); then, taking out the test matrix and washing bacteria in a suspension state by using PBS buffer solution; placing the washed test matrix in 1mL of PBS buffer solution, performing ice bath ultrasonic treatment for 15 minutes, and vibrating for 2 minutes; bacterial concentrations in PBS buffer were counted using plating.

4) Calculation of antibacterial and anti-biofilm effects: both antibacterial and anti-biofilm effects can be measured by a log reduction method:

Log reduction = log ₁₀ (number of bacteria on control/number of bacteria on modified material)

5) Verification of hydrophilicity:

2. Mu.L of deionized water was dropped on the surface of the test substrate, and the spread of the water drops was observed, wherein the negative control group was a Sylgard-184 silica gel substrate without any modification, and the test group was a Sylgard-184 silica gel substrate provided with QPVP/PEGDMA antibacterial coating (examples 1 to 4).

The verification method of contact sterilization and anti-biofilm formation can intuitively simulate the condition that the surface of the medium is in short-time contact with bacteria and the surface of the medium is in long-time contact with protein-containing body fluid of a human body when the medium is implanted into the human body. Since bacteria are widely present in the air, they are exposed to the risk of bacterial infection for a short period of time after the substrate is removed from the package and implanted into the body. The contact sterilization test can simulate the sterilization effect of the coating when the coating contacts bacteria in a short time. After the matrix is placed in the body, polysaccharide and protein in human body fluid can be slowly adhered to the surface of the substrate, so that the formation of a biological film is promoted, and in the verification of the formation of the biological film, the matrix is also soaked in a bacterial culture medium rich in protein, so that the instant and long-acting antibacterial and bactericidal effects of the coating can be proved through the two in vitro experiments.

Analysis of results:

as shown in fig. 1, the surface topography of examples 1-4 was increased relative to the uncoated control group, as observed under scanning electron microscopy for the uncoated control group and examples 1-4; wherein the roughness change of the surfaces of the examples 1,2 and 4 is not obvious, only sporadic gaps appear, but the example 3 presents a porous structure similar to hydrogel, the cross-linked coating on the surface of Sylgard-184 can reach more than 10 micrometers, and the coating which uses DADMAC monomer is thickest and can reach 20 micrometers through the observation of a scanning electron microscope on the section; this is because the DADMAC monomer used in example 3 has two propylene groups and may have higher crosslinking and polymerization efficiencies than the other monomers.

After the Sylgard-184 silica gel is modified by the coating, the hydrophilic cross-linking agent PEGDMA is introduced to obviously improve the hydrophilicity of the surface, as shown in figure 2; however, example 3, i.e., the coating to which DADMAC is applied, has the worst hydrophilicity, and also because of the specificity of the DADMAC monomer, it has a higher polymerization efficiency than PEGDMA, and thus the content of cationic polymer in the coating is relatively higher than that of the hydrophilic cross-linking agent, resulting in a decrease in the overall hydrophilicity of the coating.

The cationic hydrophilic coatings (examples 1-4) all achieved a contact sterilization effect of greater than 5.6 log reduction, i.e., a contact sterilization effect of 99.999% in three hours, as shown in fig. 3, since the cationic polymer could generate electrostatic action with the surface of the negatively charged bacterial cell membrane, and could destroy the bacterial cell membrane, thereby achieving the effect of killing bacteria, and examples 1-4 had both excellent contact sterilization effect (99.999% killing) and long-acting biofilm inhibition effect in high protein medium (TSB) due to the introduction of the hydrophilic cross-linking agent PEGDMA, as shown in fig. 4. It was found by testing that the coating had the greatest effect on the inhibition of capsular microorganisms, with respect to its hydrophilicity and roughness, and that the surface of example 3 had the greatest roughness and was the most hydrophobic, thus resulting in more protein adhesion, and that its effect on the inhibition of capsular microorganisms was the worst, only 68%. Examples 1,2 and 4 achieve an anti-capsular microorganism effect of more than 99%.

The foregoing is merely a preferred embodiment of the present invention and it should be noted that modifications and adaptations to those skilled in the art may be made without departing from the principles of the present invention, which are intended to be comprehended within the scope of the present invention.

Claims

1. A preparation method of a medical consumable substrate surface functionalization coating is characterized by comprising the following steps: the method comprises the following steps:

2. The method for preparing the functionalized coating on the surface of the medical consumable substrate according to claim 1, wherein the weakly alkaline buffer solution is any one of a phosphate buffer solution, a tris (hydroxymethyl) aminomethane buffer solution, a carbonate solution and dilute ammonia water.

3. The method for preparing the functionalized coating on the surface of the medical consumable substrate according to claim 1, wherein the compound 3 is prepared by the following steps:

s3b, modifying 4,4' -azobis (4-cyanovaleric acid) with compound 1 to produce compound 2, said compound 1 having the formula:

the compound 2 has the following chemical formula:

wherein R is an amino protecting group;

4. The method for preparing the functionalized coating on the surface of the medical consumable substrate according to claim 3, wherein the amino protecting group is Boc;

the step S3a includes the steps of:

the step S3b includes the steps of:

5. The method for preparing the functionalized coating on the surface of the medical consumable substrate according to claim 4, wherein the organic solvent 1 is any one of tetrahydrofuran, dichloromethane and ethyl acetate; the catalyst 1 is any one of triethylamine, trimethylamine, N-diisopropylethylamine and 4-dimethylaminopyridine; the organic solvent 2 is any one of ethyl acetate, toluene, methylene dichloride and chloroform; the organic solvent 3 is any one of tetrahydrofuran, dichloromethane, ethyl acetate and dimethylformamide; the catalyst 2 is any one of triethylamine, trimethylamine, N-diisopropylethylamine and 4-dimethylaminopyridine; the organic solvent 4 is any one of ethyl acetate, toluene, methylene dichloride and chloroform; the condensing agent is any one of ethyl carbodiimide hydrochloride, 1, 3-dicyclohexylcarbodiimide and N, N' -diisopropylcarbodiimide.