CN102108130A

CN102108130A - Surface biological functionalization method for hydrophobic medical high polymer materials

Info

Publication number: CN102108130A
Application number: CN 201110037602
Authority: CN
Inventors: 黄宁平; 汪燕艳; 吕兰欣
Original assignee: Southeast University
Current assignee: Southeast University
Priority date: 2011-02-14
Filing date: 2011-02-14
Publication date: 2011-06-29

Abstract

A large part of medical polymer materials is hydrophobic and inactive, so it is necessary to modify their surface with biofunctionalization to improve the biocompatibility of materials. Taking polyhydroxybutyrate valeric acid copolyester (PHBV), a biodegradable and non-immunogenic biomaterial, as an example, we propose a method for the surface biofunctionalization of a class of hydrophobic medical polymer materials by ammonia plasma Treatment or modification of dopamine can introduce amino groups on the surface of PHBV, and then the surface can be sequentially modified on the surface with polyethylene glycol molecules (NHS-PEG-MAL) and arginine-glycine-aspartic acid (RGD) molecules with different functional groups. sequence of short peptides. In vitro cell experiments and protein adsorption experiments confirmed that the biocompatibility of the modified PHBV was significantly improved. The introduced RGD short peptide can promote the growth of cells on the surface of the material, and at the same time, PEG molecules have the ability to resist non-specific protein adsorption, thereby reducing inflammation and thrombus formation.

Description

The surface biological functional method of hydrophobicity medical macromolecular materials

Technical field

What the present invention relates to is a kind of hydrophobicity medical macromolecular materials surface biological functional modification method, belongs to biomedical materials field.

Technical background

In organizational project, biomaterial is widely used in rack making.These supports not only provide mechanical support and 3D structure for cell, the signal that also provides induced tissue to form simultaneously.The structure of material, form, degraded and providing of biological activity site all are important design parameter, they all may influence the proliferation and differentiation of cell.Material surface also can be modified special biologically active substance to improve its biocompatibility.As connect the adhesion that arginine-glycine-aspartic acid (RGD) small peptide promotes cell at biomaterial surface.The RGD small peptide extensively is present in the extracellular matrix protein (as fibronectin, collagen protein and vitronectin etc.), but thereby the integrin site is connected to the cell grappling on the extracellular matrix on the specific recognition cytolemma.After being connected on the RGD small peptide, integrin can cause that thereby the variation of intracellular signaling pathway influences the propagation of cell, behaviors such as differentiation.In addition, material surface can also by modify heparin, polyoxyethylene glycol (PEG) wait and improve its anti-nonspecific proteins adsorptive power, and then reduces inflammation and takes place and thrombosis, this method is widely used in the finishing of the property implanted material such as blood vessel reparation.Polyhydroxybutyrate valeric acid copolyesters (PHBV) is a kind of good medical macromolecular materials, has biodegradability, no antigen and nontoxic, and non-carcinogenesis is subjected to extensive concern in recent years.Yet the same with most macromolecule polymer materials, the PHBV material surface is hydrophobic and lack the cell recognition site.In order further to improve the biocompatibility of PHBV, just need to change its surface property, introduce bioactive molecules, thereby reach the promotion cell adhesion, breed and increase the purpose of its anti-nonspecific proteins adsorptive power.This method can be applied to the surface modification of other hydrophobicity medical macromolecular materials equally to improve biocompatibility.

Summary of the invention

Technical problem:The object of the present invention is to provide a kind of surface modification method of hydrophobicity medical macromolecular materials, to improve the biocompatibility of material.

Technical scheme:The surface biological functional method of hydrophobicity medical macromolecular materials provided by the invention is:

At first, chosen medical macromolecular materials polyhydroxybutyrate valeric acid copolyesters PHBV, its surface hydrophobicity and reactionless avtive spot; Secondly, by Cement Composite Treated by Plasma or modification Dopamine HCL, introduce amino on the PHBV surface, carry out subsequent reactions by surface amino groups, modify successively and go up bifunctional PEG and contain the RGD small peptide, increase the active absorption that reduces nonspecific proteins simultaneously of superficial cell, improving the biocompatibility of PHBV.

Introducing amino method on the PHBV surface is: handle or modify Dopamine HCL by ammonia plasma treatment and realize; The PHBV film feeds ammonia to 50 Pa be evacuated to 7 Pa in plasma cleaner after, handles 120 sec under 60 W intensity, introduces amino on the surface; Or, the PHBV film is immersed in 24 h in the 2 mg/mL dopamine solution under room temperature, introduce amino on the surface.

Method at bifunctional PEG in the polyhydroxybutyrate valeric acid copolyesters PHBV modification is: the PHBV after will being modified with amino is immersed in 1 h in the 2 mM bifunctional PEG reaction solns under room temperature, and bifunctional PEG is covalently bound to the surface.

The method that contains the RGD small peptide in modification on the bifunctional PEG is: the PHBV film after will modifying bifunctional PEG is immersed in 5 h in the 50 μ g/mL RGD small peptide solution under room temperature, and the RGD small peptide is covalently bound to the surface.

Beneficial effect:The invention has the advantages that by easy method on hydrophobicity medical macromolecular materials surface

Introduce active function groups, and then modify PEG molecule with anti-nonspecific proteins absorption and the RGD small peptide that can promote the cell growth successively, thereby significantly improve raw-material biocompatibility by this functional group.

Description of drawings

Fig. 1 is the synoptic diagram of PHBV membrane prepare and surface biological functional method.

Fig. 2 is the active comparison of PHBV film superficial cell before and after modifying.

Fig. 3 is the comparison of the former adsorptive power of PHBV film surface antifibrin before and after modifying.

Fig. 4 is the comparison of PHBV film surface antiserum(antisera) protein adsorption ability before and after modifying.

Embodiment

1) prepares the PHBV film with spin-coating method; PHBV is dissolved in chloroform, and concentration is 10 (w/v) %, and is even by magnetic stirrer.Prepare the PHBV film with spin-coating method in surface of glass slide: with clean slide (Φ: 10 mm) place sol evenning machine, get 60 μ L PHBV drips of solution to surface of glass slide, with 4000 rpm spin coatings, 30 sec.Then spin coating there is the slide of PHBV film to put into 60 ℃ of vacuum-dryings of vacuum drying oven and spends the night, remove remaining chloroform.

2) at PHBV film finishing amino: (a) introduce amino by ammonia plasma treatment method treat surface: the PHBV film for preparing is put into plasma cleaner, be evacuated to 7 Pa, feed ammonia to 50 Pa, 60 W handle 120 sec.Perhaps (b) introduces amino by Dopamine HCL on the surface: get 40 mg Dopamine HCLs and be dissolved in 20 mL, 10 mM Tris-HCl damping fluids (pH 8.5) and be made into reaction solution, the PHBV film is put into reaction solution, reaction 24 h under the room temperature, the back dries up with a large amount of ultrapure water flushing surfaces and with nitrogen.

3) be modified with amino PHBV film finishing NHS-PEG-MAL: NHS-PEG-MAL is dissolved in HEPES-NaCl damping fluid (pH 7.2 for 10 mM HEPES, 150 mM NaCl), is made into the reaction solution that concentration is 2 mM; Immerse in the reaction solution reaction 1 h under the room temperature, the back unreacted NHS-PEG-MAL solution of ultrapure water flush away with being modified with amino PHBV film.

4) introduce GRGDSPC after modifying NHS-PEG-MAL: GRGDSPC is dissolved in HEPES-NaCl-EDTA damping fluid (5 mM EDTA, pH 6.8 for 10 mM HEPES, 150 mM NaCl), and concentration is 50 μ g/mL; PHBV film behind the modification NHS-PEG-MAL is immersed in this solution reaction 5 h under room temperature, the GRGDSPC of back on the ultrapure water flush away unreacted.

5) each step is reacted the back by contact angle, and XPS detects proof PHBV surface and successfully modifies amino, NHS-PEG-MAL and GRGDSPC, and after soaking 3 days, surface group is stable.Obviously strengthen (Fig. 2) from NIH 3T3 cell culture experiments and nonspecific proteins adsorption experiment are provable modifying RGD rear surface cytoactive than the surface of unmodified; Modify the anti-nonspecific proteins adsorptive power in NHS-PEG-MAL rear surface and obviously strengthen, after introducing RGD, the surface still have this characteristic (Fig. 3, Fig. 4).So after this method modification, the biocompatibility of PHBV significantly improves.

Claims

1. the surface biological functional method of hydrophobicity medical macromolecular materials is characterized in that: at first, chosen medical macromolecular materials polyhydroxybutyrate valeric acid copolyesters PHBV, its surface hydrophobicity and reactionless avtive spot; Secondly, by Cement Composite Treated by Plasma or modification Dopamine HCL, introduce amino on the PHBV surface, carry out subsequent reactions by surface amino groups, modify successively and go up bifunctional PEG and contain the RGD small peptide, increase the active absorption that reduces nonspecific proteins simultaneously of superficial cell, improving the biocompatibility of PHBV.

2. the surface biological functional method of hydrophobicity medical macromolecular materials according to claim 1 is characterized in that introducing amino method on the PHBV surface is: handle or modify Dopamine HCL by ammonia plasma treatment and realize; The PHBV film feeds ammonia to 50 Pa be evacuated to 7 Pa in plasma cleaner after, handles 120 sec under 60 W intensity, introduces amino on the surface; Or, the PHBV film is immersed in 24 h in the 2 mg/mL dopamine solution under room temperature, introduce amino on the surface.

3. the surface biological functional method of hydrophobicity medical macromolecular materials according to claim 1, it is characterized in that in the method for bifunctional PEG in the polyhydroxybutyrate valeric acid copolyesters PHBV modification being: the PHBV after will being modified with amino is immersed in 1 h in the 2 mM bifunctional PEG reaction solns under room temperature, and bifunctional PEG is covalently bound to the surface.

4. the surface biological functional method of hydrophobicity medical macromolecular materials according to claim 3, it is characterized in that the method that contains the RGD small peptide in modification on the bifunctional PEG is: the PHBV film after will modifying bifunctional PEG is immersed in 5 h in the 50 μ g/mL RGD small peptide solution under room temperature, and the RGD small peptide is covalently bound to the surface.