CN106280977B - Silicone rubber antibacterial coating - Google Patents

Abstract

The invention relates to a silicone rubber antibacterial coating which is prepared by the following method: A. dissolving a chlorhexidine product in ethyl acetate; B. diluting the organosilicon adhesive MDX4-4210 by using an organosilicon solvent Q7-2650; C. mixing the two components according to the required chlorhexidine concentration, adding the MDX4-4210 catalyst, and stirring uniformly. The coating can be coated on the surface of a silicon rubber medical appliance, and has the functions of adding antibacterial, antifungal and other disease-treating microorganisms to the original appliance. This patent combines together chlorhexidine class antibiotic substance and hydrophobic silica gel material, reaches the purpose that promotes current silica gel class medical instrument additional function.

Description

Silicone rubber antibacterial coating

Technical Field

The invention relates to a silicone rubber coating, in particular to a silicone rubber coating containing an antibacterial agent.

Background

At present, plastic and rubber polymer products are widely applied to various fields, and are particularly widely applied to the medical field, and besides materials such as metal, glass and the like, the medical products are made of polymer materials in a high proportion. With the development of medical technology, interventional therapy catheters are widely used in clinical treatment. Many medical devices, such as catheters, guide wires, etc., which need to be in contact with human tissues for a short time or a long time, carry pathogenic microorganisms and propagate and proliferate to cause infection when being inserted or pulled out and staying in the human body, so that the medical devices can cause damage to the tissues and further cause adverse reactions such as inflammation. Therefore, in order to reduce the risk of operation and relieve the pain of patients, preoperative or postoperative oral antibacterial drugs are needed. This also causes clinical problems such as bacterial resistance due to overuse of antibiotics. Due to the unique hydrophobic property of the silica gel surface, it is difficult to directly insert the antibacterial component into the silica gel surface.

PCT patent publication No. WO 2010/151682a2, published 12/29/2010, provides a method for obtaining a sustained-release chlorhexidine from a silicone material by soaking the silicone material in a chlorhexidine solution of a certain concentration for a certain period of time. The silicone material obtained by the method has a layer of chlorhexidine solution adhered on the surface, wherein the silicone material and the chlorhexidine are combined together in an adsorption mode, the binding force is very weak, the release speed is very fast when the silicone material is released, and then the silicone material is rapidly reduced, so that the concentration of the chlorhexidine in the surrounding solution is very high when the silicone material is used, but the concentration is rapidly reduced, and the slow release effect is very poor. And in a body fluid environment, the drug is very easily dissolved away, causing the peak of release to appear early and decrease immediately abruptly. In the process of preparing the antibacterial polymer by the dipping method, the dipping time is as long as 24 hours or even 48 hours, which is inconvenient to use. Moreover, the antibacterial polymer prepared by soaking and adsorbing the antibacterial agent is easy to peel off the antibacterial agent on the surface when the device such as a catheter and the like is packed and transported and inserted into a body.

Disclosure of Invention

The invention aims to provide a silicone rubber antibacterial coating which is strong in binding force between chlorhexidine and silicone rubber and is not easy to fall off.

The silicone rubber antibacterial coating is prepared by the following method:

A. dissolving chlorhexidine or a chlorhexidine derivative in a solvent;

B. the MDX4-4210 adhesive was diluted with diluent Q7-2650.

C. And C, mixing the liquid obtained in the step A and the liquid obtained in the step B, adding an MDX4-4210 catalyst, and uniformly mixing.

The solvent used in the step A is preferably ethyl acetate, and other solvents having good solubility compatibility with siloxane and chlorhexidine can be selected.

The chlorhexidine derivative in step a may be chlorhexidine gluconate or chlorhexidine hydrochloride, or other chlorhexidine derivatives with antibacterial function.

In the step B, the mixing ratio of the diluent Q7-2650 to the MDX4-4210 adhesive is (10: 1-1: 1), preferably 4:1, and can be adjusted according to the thickness requirement of the final coating.

The concentration of the chlorhexidine in the step A can be adjusted according to the requirement of the final antibacterial situation; the mixing ratio of the two liquids in step A and step B described in step C can also be adjusted according to the requirements of the final antibacterial situation.

The surface fastness test of the coating prepared by the method has the first-grade result, and no visible coating falls off.

The test method is a TQC adhesion cross-cut test.

In the invention, the diluent Q7-2650 is a medical organic silicon solvent produced by Dow Corning company, and the MDX4-4210 is a medical two-component silicon-based adhesive produced by Dow Corning company, and is divided into two independent packaging components of the adhesive and the catalyst, namely MDX4-4210 adhesive and MDX4-4210 catalyst.

Detailed Description

The present invention will be described in further detail with reference to examples.

Example 1

The silicone rubber antibacterial coating is prepared by the following method:

A. chlorhexidine was dissolved in ethyl acetate at a concentration of 20 mg/ml;

B. taking 40ml of diluent Q7-2650 and 10ml of MDX4-4210 adhesive, uniformly mixing the diluent Q7-2650 and the adhesive, adding 8ml of the chlorhexidine ethyl acetate solution with the concentration of 20mg/ml prepared in the step A, and uniformly mixing;

C. mixing an MDX4-4210 adhesive and an MDX4-4210 catalyst 50: 1, adding 0.2ml of MDX4-4210 silica gel catalyst into the liquid obtained at the end of the step B, and uniformly mixing;

C. and adding a certain amount of chlorhexidine solution into the mixture of the silica gel adhesive, and uniformly stirring to obtain the silicone rubber antibacterial coating.

And sealing one end of the silicone tube, soaking the silicone tube in the silicone rubber antibacterial coating prepared according to the steps, keeping the silicone tube for 10 seconds, taking out the silicone rubber antibacterial coating, hanging and drying the silicone tube for 16 hours at room temperature, curing and drying the adhesive, and then carrying out vacuum drying at room temperature for 4 hours to fix the coating on the surface of the silicone tube. The silicone tube is NALGENE50 silicone tube manufactured by NALGENE company, and the trade mark is 8060-0030.

The effect of the coating fixed on the surface of the silica gel is first grade through the surface fastness test of the coating, and no visible coating falls off. The test instrument and the method comprise the following steps: TQC Adhesion Cross Cut Test (TQC Cross Cut Adhesion Test).

The concentration of the ethyl acetate solution of chlorhexidine in step a above may be configured according to the concentration of chlorhexidine required for antimicrobial properties in the final coating.

When the volume ratio of the diluent Q7-2650 to the MDX4-4210 binder is in the range of (10: 1-1: 1), the fixing effect of the coating on the surface of the silica gel is first grade through a fastness test according to the detection of the steps.

Claims (1)

1. A silicone rubber antibacterial coating is prepared by the following steps:

A. dissolving chlorhexidine or chlorhexidine derivative in 20mg/ml solvent, wherein the solvent is ethyl acetate;

B. diluting the MDX4-4210 adhesive by using a diluent Q7-2650, wherein the mixing ratio of the diluent Q7-2650 to the MDX4-4210 adhesive is 4: 1;

C. and C, mixing the liquid obtained in the step A and the liquid obtained in the step B, adding an MDX4-4210 catalyst, and uniformly mixing.