CN112245657A

CN112245657A - Low-heat-release antibacterial bone cement and preparation method and application thereof

Info

Publication number: CN112245657A
Application number: CN202011120695.9A
Authority: CN
Inventors: 李闯; 傅尧
Original assignee: Huzhou Mammoth Medical Technology Co ltd
Current assignee: Hefei Zhongke Zhiyuan Biotechnology Co ltd
Priority date: 2020-10-19
Filing date: 2020-10-19
Publication date: 2021-01-22
Anticipated expiration: 2040-10-19
Also published as: CN112245657B

Abstract

The invention discloses low-heat-release antibacterial bone cement, which relates to the technical field of medical materials and comprises powder and liquid, wherein the powder comprises PMMA powder with high molecular weight, benzoyl peroxide, a contrast agent and hydroquinone; the liquid agent comprises methyl methacrylate monomer and furfuryl methacrylate. The invention also provides a preparation method and application of the low-heat-release antibacterial bone cement. The invention has the beneficial effects that: the bone cement of the invention is prepared by stirring the powder and the liquid and then curing the mixture after stirring, and the cured bone cement has high antibacterial activity, low exothermicity and good biocompatibility.

Description

Low-heat-release antibacterial bone cement and preparation method and application thereof

Technical Field

The invention relates to the technical field of medical materials, in particular to low-heat-release antibacterial bone cement and a preparation method and application thereof.

Background

PMMA bone cement (polymethyl methacrylate) is the most clinically applied bone cement at present, and consists of powder and liquid. The powder has PMMA as main component and the liquid has MMA monomer. The PMMA bone cement used clinically at present has poor antibacterial performance, so PMMA can increase the risk of infection due to bacterial invasion and biofilm formation on the surface of PMMA.

When the bone cement is used as a bone repair material, antibiotics are injected into the bone cement or the bone cement is loaded with the antibiotics, resistance is easy to generate, and the local high concentration can cause damage to the surrounding joint tissues. Due to the unreasonable use of antibiotics, the clinical use of drug-resistant bacteria (such as drug-resistant staphylococcus aureus MRSA, drug-resistant staphylococcus epidermidis MRSE and the like) is gradually increased, and the conventional implanted antibiotic bone cement is difficult to apply. In addition, since the harm of antibiotics to human body is increasingly obvious, the reduction of the use of antibiotics has become an important treatment principle. The existence of these outstanding problems greatly limits the clinical application and popularization of antibiotic bone cement.

For example, patent application with publication number CN107982576A discloses a bone cement and a preparation method thereof, wherein the bone cement mainly comprises powder and liquid, and the prepared bone cement has the characteristics of good antibacterial property, good injectability and the like, and also has good biocompatibility and osteoinductivity. However, in the prior art, the traditional PMMA bone cement releases heat in the polymerization process to cause local temperature as high as 100 ℃, and peripheral nerve function damage or necrosis and the like are easily caused. Therefore, there is an urgent clinical need to develop new anti-infective, low-exothermic PMMA bone cement materials that are not based on antibiotics.

Disclosure of Invention

The invention aims to solve the technical problem that the PMMA bone cement in the prior art releases heat in the polymerization process to cause over-high local temperature, and peripheral nerve function damage or necrosis is easy to cause.

The invention solves the technical problems through the following technical means:

the invention provides low-heat-release antibacterial bone cement which comprises powder and liquid, wherein the powder comprises PMMA powder with high molecular weight, benzoyl peroxide, a contrast agent and hydroquinone; the liquid agent comprises methyl methacrylate monomer and furfuryl methacrylate.

Has the advantages that: the bone cement of the invention is prepared by stirring the powder and the liquid and then curing the mixture after stirring, and the cured bone cement has high antibacterial activity, low exothermicity and good biocompatibility.

Preferably, the mass ratio of the powder to the liquid is 1: 0.5-1.

Has the advantages that: if the mass ratio of the liquid to the powder is higher than 1:1, the curing time is prolonged by 5-10min, the operation risk is increased, and meanwhile, the monomer reaction is incomplete, and the toxicity risk in vivo is increased; if the mass ratio of the powder and the liquid is higher than 2:1, the injectability of the bone cement is affected.

Preferably, the powder is mainly prepared from the following raw materials in parts by weight:

preferably, the liquid agent is mainly prepared from the following raw materials in percentage by volume: 80-99% of methyl methacrylate monomer and 1-20% of furfuryl methacrylate.

Has the advantages that: powder and liquid formulations are within the above ranges, and the materials act synergistically, and ratios outside the ranges affect injectability and increase toxicity risks.

Preferably, the molecular weight of the high molecular weight PMMA powder is 30 to 50 ten thousand.

Has the advantages that: the molecular weight of PMMA powder is lower than 30 ten thousand, the strength of the bone cement is relatively low, and the requirements on mechanical properties cannot be met; the molecular weight is more than 50 ten thousand, the viscosity of PMMA is increased, and the injectability in clinical use is influenced.

Preferably, the contrast agent comprises one or both of barium sulfate and cobalt dioxide.

Preferably, the liquid agent further comprises N, N-dimethyl-p-toluidine, and the volume ratio of the N, N-dimethyl-p-toluidine to the methyl methacrylate monomer and the furfuryl methacrylate is 1: 100.

Preferably, the preparation method of the powder comprises the following steps: mixing PMMA powder with high molecular weight, benzoyl peroxide, a contrast agent and hydroquinone, and sterilizing to obtain the bone cement powder.

Preferably, the preparation method of the liquid agent comprises the following steps: mixing methyl methacrylate monomer and furfuryl methacrylate to obtain the liquid for bone cement.

The invention also provides a preparation method of the low-heat-release antibacterial bone cement, which comprises the following steps;

(1) mixing PMMA powder with high molecular weight, benzoyl peroxide, a contrast agent and hydroquinone, and sterilizing to obtain bone cement powder;

(2) mixing methyl methacrylate monomer and furfuryl methacrylate to obtain liquid for bone cement;

(3) and (3) mixing the powder in the step (1) and the liquid in the step (2) to obtain the bone cement.

Has the advantages that: the preparation method of the bone cement is simple, can prepare any plastic bone cement, and has wide application.

The invention also provides application of the low-heat-release antibacterial bone cement in an orthopedic implant material.

The invention has the advantages that:

(1) the bone cement contains the bio-based antibacterial monomer of the furfuryl methacrylate, so that the antibacterial performance of the PMMA bone cement is greatly improved, the heat release of the bone cement is reduced, the bone cement is proved to be non-toxic through a cytotoxicity experiment, and a hemolysis experiment result shows that the PMMA bone cement has good compatibility with blood; can not cause drug resistance of human body.

(2) The preparation method of the bone cement is simple, can prepare the bone cement with any shape, and has wide application.

(3) The bone cement can be applied to orthopedic implant materials, has high antibacterial activity, can reduce the use of antibiotics, and cannot cause drug resistance of human bodies.

Drawings

FIG. 1 is a graph showing the results of cell viability assay of bone cements in example 1 and comparative example 1 of the present invention;

FIG. 2 is a graph showing the results of measuring the hemolysis ratio in example 1 of the present invention and comparative example 1.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention, and it is obvious that the described embodiments are some embodiments of the present invention, but not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Test materials, reagents and the like used in the following examples are commercially available unless otherwise specified.

The specific techniques or conditions not specified in the examples can be performed according to the techniques or conditions described in the literature in the field or according to the product specification.

Example 1

The low-heat-release antibacterial bone cement comprises liquid and powder; the powder consisted of 1.8g of PMMA powder with a molecular weight of 40 ten thousand, 0.18g of barium sulfate, 0.02g of benzoyl peroxide and 0.02g of hydroquinone (BPO); the liquid formulation included 0.9mL of methyl methacrylate and 0.1mL of furfuryl methacrylate.

The preparation method of the low-heat-release antibacterial bone cement comprises the following steps: stirring and mixing the raw materials in the liquid, stirring and mixing the raw materials in the powder, mixing the raw materials in the liquid, adding 10uL of N, N-dimethyl-p-toluidine (DMPT), stirring and mixing the powder and the liquid according to the mass ratio of 1:0.5, and performing injection molding through an injector. Wherein DMPT catalyzes BPO to generate free radicals.

Example 2

The low-heat-release antibacterial bone cement comprises liquid and powder; the powder comprises 1.4g of PMMA powder with the molecular weight of 30 ten thousand, 0.16g of barium sulfate, 0.06g of benzoyl peroxide and 0.04g of hydroquinone; the liquid formulation included 0.8mL of methyl methacrylate and 0.2mL of furfuryl methacrylate.

The preparation method of the low-heat-release antibacterial bone cement comprises the following steps: stirring and mixing the raw materials in the liquid, stirring and mixing the raw materials in the powder, mixing the raw materials in the liquid, adding 10uL of N, N-dimethyl-p-toluidine (DMPT), stirring and mixing the powder and the liquid according to the mass ratio of 1:0.5, and performing injection molding through an injector.

Example 3

The low-heat-release antibacterial bone cement comprises liquid and powder; the powder comprises 1.6g of PMMA powder with the molecular weight of 50 ten thousand, 0.18g of barium sulfate, 0.07g of benzoyl peroxide and 0.06g of hydroquinone; the liquid formulation included 0.99mL of methyl methacrylate and 0.01mL of furfuryl methacrylate.

The preparation method of the low-heat-release antibacterial bone cement comprises the following steps: stirring and mixing the raw materials in the liquid, stirring and mixing the raw materials in the powder, mixing the raw materials in the liquid, adding 10uL of N, N-dimethyl-p-toluidine (DMPT), stirring and mixing the powder and the liquid according to the mass ratio of 1:0.8, and performing injection molding through an injector.

Example 4

This embodiment is different from embodiment 1 in that: the mass ratio of the powder to the liquid is 1: 1.

Example 5

This embodiment is different from embodiment 1 in that: the molecular weight of PMMA is 30 ten thousand.

Example 6

This embodiment is different from embodiment 1 in that: the molecular weight of PMMA is 50 ten thousand.

Comparative example 1

This comparative example differs from example 1 in that: the liquid agent is methyl methacrylate.

Comparative example 2

This comparative example differs from example 1 in that: the molecular weight of PMMA is 20 ten thousand.

Comparative example 3

This comparative example differs from example 1 in that: the molecular weight of PMMA is 60 ten thousand.

Example 7

The cytotoxicity, hemolytic rate, antibacterial property, and exothermic temperature of the bone cement after curing in example 1 and comparative example 1 were measured.

The method for measuring cytotoxicity comprises the following steps:

(1) solidifying the bone cement into a cylinder with the height of 6mm and the diameter of 6.5 mm;

(2) preparing a leaching solution: after each bone cement sample was soaked in alcohol and Phosphate Buffered Saline (PBS) for 24 hours, the two groups of leaching solutions of the bone cements of comparative example 1 and example 1 were obtained by soaking the bone cement samples in complete medium for 24 hours.

(3) Inoculation of cells: complete medium was used as a blank, and 5000-10000 human osteoblasts (HFOB) were inoculated into each well at 37 ℃ with 5% CO₂Cell viability (MTT) was measured after 24 and 48 hours of incubation in ambient conditions.

And (3) measuring results: as shown in fig. 1, the cell viability was higher than 80% for both example 1 and comparative example 1 relative to the blank, indicating that the material was non-toxic.

(II) hemolysis rate determination method:

(1) solidifying the bone cement into a cylinder with the height of 10mm and the diameter of 10 mm;

(2) and (3) preparing a leaching solution, namely soaking each bone cement sample in alcohol for 24 hours, and then soaking the bone cement sample in Phosphate Buffer Solution (PBS) at 37 ℃ for 48 hours according to the proportion of 0.5mL/g to obtain the leaching solution.

(3) Bone cement PBS extract, PBS (negative control) and double distilled water (positive control), 5 each, 2mL per tube, were added.

(4) 2mL of 2% fresh healthy human blood suspension is added into each tube respectively, after incubation for 4 hours at 37 ℃, centrifugation is carried out for 5min at 1000r/min, 1mL of supernatant is taken, and the absorbance of each sample at 540nm is measured under an enzyme-linked immunosorbent assay.

(5) Calculation of the hemolysis rate: hemolysis rate (sample absorbance-negative control absorbance)/(positive control absorbance-negative control absorbance).

And (3) measuring results: as shown in fig. 2, the hemolysis rate of the bone cement in both comparative example 1 and example 1 is less than 5%, and the hemolysis rate in example 1 is lower, indicating that the bone cement in both comparative example 1 and example 1 has good blood compatibility, and the compatibility of example 1 is better.

(III) the method for measuring the antibacterial rate comprises the following steps:

(1) solidifying the bone cement into a cylinder with the height of 5mm and the diameter of 6 mm;

(2) preparing a leaching solution: the bone cement samples were sterilized by soaking in alcohol for 24 hours.

(3) Escherichia coli (Escherichia coli ATCC25922), Staphylococcus aureus (Staphylococcus aureus ATCC25923) and Staphylococcus epidermidis (Staphylococcus epidermidis ATCC12228) were planted on the surfaces of the two groups of bone cements. After 24 hours, the adhesion and the death of bacteria on the surface of the bone cement are observed by using live bacteria staining.

The calculation method comprises the following steps:

the sterilization rate (%) is [ ("control sample viable cell count-bone cement viable cell count)/control sample viable cell count ] × 100, the control sample viable cell count is the viable cell count after bacterial culture on a control sample (the control sample is a culture medium), and the bone cement viable cell count is the viable cell count after bacterial culture on bone cement.

And (3) measuring results: as shown in table 1, it can be seen that the bone cement of example 1 has a superior antibacterial property.

Table 1 shows the results of the measurement of the antibacterial property of the bone cements in comparative example 1 and example 1

	The bactericidal activity of Escherichia coli/%)	Staphylococcus aureus/%)	Staphylococcus epidermidis/%)
				Example 1	97.3	98.1	98.5
Comparative example 1	54.5	55.6	54.9

(IV) exothermic temperature measuring method:

the powder and the liquid in example 1 and comparative example 1 were mixed and stirred, respectively, and the peak exothermic temperature of the cement during the setting and molding process was measured.

And (3) measuring results: as shown in table 2, it can be seen that the addition of the furfuryl methacrylate monomer in example 1 significantly reduces the curing exotherm of the bone cement during the curing and forming process.

Table 2 shows the results of the measurement of the exothermic heat of setting of the bone cement in example 1 and comparative example 1

	Highest temperature/DEG C in the process of bone cement solidification
		Example 1	56.0
Comparative example 1	88.6

Example 8

The bone cements prepared in example 5, example 6, comparative example 2 and comparative example 3 were measured for mechanical strength and injection properties, wherein the mechanical property test method was according to the compression strength test method specified in ISO5833 and ASTM F451.

The measurement results are shown in Table 3.

Table 3 shows the results of measuring the properties of the bone cements obtained in examples 5 to 6 and comparative examples 2 to 3

Molecular weight of PMMA	Mechanical strength	Injection performance
				20 ten thousand	65.8MPa	Low viscosity and good injectability
30 ten thousand	81.1MPa	Low viscosity and good injectability
			50 ten thousand	90.4MPa	High viscosity and poor injectability
60 ten thousand	93.9MPa	Excessive viscosity and no possibility of injection

The above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.

Claims

1. A low-heat-release antibacterial bone cement is characterized in that: comprises powder and liquid, wherein the powder comprises PMMA powder with high molecular weight, benzoyl peroxide, contrast agent and hydroquinone; the liquid agent comprises methyl methacrylate monomer and furfuryl methacrylate.

2. A low exothermic antibacterial bone cement according to claim 1, wherein: the mass ratio of the powder to the liquid is 1: 0.5-1.

3. A low exothermic antibacterial bone cement according to claim 1, wherein: the powder is mainly prepared from the following raw materials in parts by weight:

4. a low exothermic antibacterial bone cement according to claim 3, wherein: the molecular weight of the PMMA powder with high molecular weight is 30-50 ten thousand.

5. A low exothermic antibacterial bone cement according to claim 3, wherein: the contrast agent comprises one or two of barium sulfate and cobalt dioxide.

6. A low exothermic antibacterial bone cement according to claim 1, wherein: the liquid agent is mainly prepared from the following raw materials in percentage by volume: 80-99% of methyl methacrylate monomer and 1-20% of furfuryl methacrylate.

7. A low exothermic antibacterial bone cement according to claim 1, wherein: the preparation method of the powder comprises the following steps: the liquid agent also comprises N, N-dimethyl-p-toluidine, and the volume ratio of the N, N-dimethyl-p-toluidine to the methyl methacrylate monomer and the furfuryl methacrylate is 1: 100.

8. A low exothermic antibacterial bone cement according to claim 1, wherein: the preparation method of the powder comprises the following steps: mixing PMMA powder with high molecular weight, benzoyl peroxide, a contrast agent and hydroquinone, and sterilizing to obtain the bone cement powder.

9. A method for preparing a low exothermic antibacterial bone cement according to any one of claims 1 to 7, characterized in that: the method comprises the following steps:

10. Use of a low exothermic antibacterial bone cement according to any one of claims 1 to 6 in an orthopaedic implant material.