首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
Poly (3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx), a polyester with strong mechanical properties and biocompatibility, is a member of microbial polyhydroxyalkanoates (PHA) family. Maleic anhydride was used to graft PHBHHx to form maleated PHBHHx (Ma-PHBHHx). Ma-PHBHHx with a graft degree of 0.59% was found to be more thermo-stable in comparison with PHBHHx. In vitro study demonstrated that the biocompatibility to mouse fibroblast L929 and human microvascular endothelial cells (HMEC) was improved in different degrees on Ma-PHBHHx films and scaffolds. Compared with their growth on PHBHHx, L929 and HMEC grown on Ma-PHBHHx films and scaffolds showed approximately 120% and 260% more in proliferation rates, respectively. Morphology study suggested that fine whorl-like surface structures with porosities on Ma-PHBHHx films attributed to MA grafting would be better for cell attachment and proliferation. Ma-PHBHHx scaffolds prepared by thermally induced phase separation (TIPS) with increased porosity, hydrophilicity, surface energy, and charges also were more favorable for cell growth. In addition, Ma-PHBHHx showed an accelerated degradation incubation in SBF at 37 degrees C, losing 21.4% of its original weight after 21 weeks while PHBHHx just lost 7.3%. Based on the improved biocompatibility, reasonable mechanical properties as well as accelerated biodegradation, Ma-PHBHHx has shown advantages over PHBHHx as a biomaterial for biomedical applications.  相似文献   

2.
Wang YW  Wu Q  Chen J  Chen GQ 《Biomaterials》2005,26(8):899-904
Hydroxyapatite (HAP) was blended into poly(3-hydroxybutyrate) (PHB) and poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) to make films and scaffolds. After HAP blending, mechanical properties of PHB including compressive elastic modulus and maximum stress showed improvement and osteoblast responses including cell growth and alkaline phosphatase activity were also strengthened. On the other hand, scaffolds made of PHBHHx blended with HAP had an adverse effect. No remarkable change on degradation of PHB or PHBHHx blended with HAP, respectively, was observed in simulated body fluid. Scanning electron microscopy examination revealed that osteoblast responses to HAP incorporation may be related to surface morphology and to the exposed HAP particles on polymer surface. All these results indicated that the blending of HAP particles into PHBHHx scaffolds fabricated by salt leaching was unable to either strengthen its mechanical properties or enhance osteoblast responses. Although HAP is bioactive and osteoconductive, its blending with PHBHHx did not generate a better performance on bone reconstruction.  相似文献   

3.
A terpolyester consisting of 3-hydroxybutyrate (3HB), 4-hydroxybutyrate (4HB) and 3-hydroxyhexanoate (3HHx), abbreviated as P(3HB-co-4HB-co-3HHx), was studied for possible application as an implant biomaterial. L929 mouse fibroblasts, MC3T3-E1 murine osteoblasts and a human cell line of immortalized human keratinocyte (HaCat cells) were used to study the biocompatibility of P(3HB-co-4HB-co-3HHx). Cell morphology and cell activity were studied using scanning electron microscopy (SEM) and the MTT assay, respectively. All three cell types showed higher activities when grown on films of P(3HB-co-4HB-co-3HHx) compared with their growth on poly(lactic acid) (PLA), co-polyester PHBHHx films and on polylysine-coated plates (blank), respectively. The three cell types grown on the terpolyester also demonstrated a well-spread cell shape and large number of pseudopods due to strong cell-cell and cell-material interactions. It was clearly observed that P(3HB-co-4HB-co-3HHx) had a much faster degradation rate than PHBHHx after 15 weeks of incubation in phosphate-buffered saline under dynamic conditions. The results proved that the terpolyester had favorable biocompatibility and biodegradability compared with the well-studied polyesters PLA and PHBHHx.  相似文献   

4.
Wang YW  Yang F  Wu Q  Cheng YC  Yu PH  Chen J  Chen GQ 《Biomaterials》2005,26(7):755-761
Films made of poly (3-hydroxybutyrate) (PHB), poly(3-hydroxybutyrate- co-3-hydroxyhexanoate) (PHBHHx) consisting of 5%, 12% and 20% hydroxyhexanoate (HHx), respectively, were evaluated for biomedical application in comparison with poly (L-Lactide) (PLA). With the increase of HHx content in PHBHHx, the polymer surface properties changed accordingly. P(HB-co-20%-HHx) had the smoothest surface while PHB surface was most hydrophilic among the evaluated PHB and all the PHBHHx. All PHBHHx also showed strong protein affinity and biocompatibility. It was found that fibroblast and osteoblast had different responses to these polymers: fibroblast cells favored P(HB-co-20%-HHx), yet osteoblast cells preferred P(HB-co-12%-HHx). PHB and all PHBHHx appeared to have better biocompatibility for fibroblast and osteoblast compared with PLA. Polymers possessing different surface properties may help meet different cellular requirements. Combined with their good mechanical properties for elongation and adjustable biocompatibility, PHBHHx may meet the needs of growth requirements of different tissues and cells.  相似文献   

5.
A terpolyester consisting of 3-hydroxybutyrate (3HB), 4-hydroxybutyrate (4HB) and 3-hydroxyhexanoate (3HHx), abbreviated as P(3HB-co-4HB-co-3HHx), was studied for possible application as an implant biomaterial. L929 mouse fibroblasts, MC3T3-E1 murine osteoblasts and a human cell line of immortalized human keratinocyte (HaCat cells) were used to study the biocompatibility of P(3HB-co-4HB-co-3HHx). Cell morphology and cell activity were studied using scanning electron microscopy (SEM) and the MTT assay, respectively. All three cell types showed higher activities when grown on films of P(3HB-co-4HB-co-3HHx) compared with their growth on poly(lactic acid) (PLA), co-polyester PHBHHx films and on polylysine-coated plates (blank), respectively. The three cell types grown on the terpolyester also demonstrated a well-spread cell shape and large number of pseudopods due to strong cell–cell and cell–material interactions. It was clearly observed that P(3HB-co-4HB-co-3HHx) had a much faster degradation rate than PHBHHx after 15 weeks of incubation in phosphate-buffered saline under dynamic conditions. The results proved that the terpolyester had favorable biocompatibility and biodegradability compared with the well-studied polyesters PLA and PHBHHx.  相似文献   

6.
Samples of polyhydroxybutyrate (PHB), poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) and poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) containing 4–20% (mol/mol) 3-hydroxyhexanoate (3HHx) were characterized as potential components of blood-contact biomaterials. In an erythrocyte contact hemolysis assay, all tested PHBHHx films had substantially reduced reactivity, typically displaying about 2-fold less hemolytic activity compared with that of PHBV. Both 12% and 20% containing PHBHHx also bound less platelets than other films. After a 120-min exposure to platelet-rich plasma (PRP), few platelets adhered to the 12% and 20% containing PHBHHx films, while numerous platelets were seen on PHBV. Surface properties investigation suggested along with increasing 3HHx content, PHBHHx co-polymer films became smoother and smoother, which may contribute to lower platelet adhesion of PHBHHx containing high HHx content in a short-term contact to platelet-rich plasma. In a long-term contact to PRP, the difference in crystallization of PHBVand PHBHHx can be a critical parameter for platelet adhesion. Human umbilical vein endothelial cells (HUVECs) grew well on PHBHHx containing high content of 3HHx, indicating that both had good biocompatibility with HUVECs. While gelatin-coated or lipase-treated polyesters improved HUVECs proliferation compared with that on uncoated films, platelet adhesion was also decreased on gelatin-coated polyester. The hemocompatibility and biocompatibility of PHBHHx film were markedly improved. Thus, PHBHHx, particularly the surface-modified PHBHHx film, is promising for blood-contact materials.  相似文献   

7.
Poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) and PHBHHx-hydroxyapatite (HAP) composite scaffolds have been prepared by phase separation and subsequent sublimation of the solvent for bone tissue engineering. Scanning electron microscopy (SEM), porosity measurement, mechanical tests, and thermogravimertric analysis (TGA) are used to analyze the physical properties of the scaffolds. The biocompatibility and osteoconductivity are assessed by examining the morphology, proliferation, and differentiation of MC3T3-E1 osteoprogenitor cells seeded on the scaffolds. The PHBHHx-HAP composite scaffolds show better mechanical properties, biocompatibility, and osteoconductivity than the PHBHHx scaffolds. The results suggest that PHBHHx-HAP composite scaffolds can be employed as a promising candidate for bone reconstruction.  相似文献   

8.
The new biodegradable polyester poly(3-hydroxybutyrate-co-3-hydroxyhexnoate) (PHBHHx) has a potential application in tissue engineering. The aim of this study was to present a deeper picture of the relationship between the cellular behavior and the surface characteristics of PHBHHx films. The pristine PHBHHx film was prepared by adopting the compression-molding method, and then the acrylic acid molecules were grafted on PHBHHx membrane surface by UV irradiation. The hydrophilic nature and surface roughness of various PHBHHx films were controlled by adjusting the acrylic acid concentration and the UV irradiation time. Although the surface characteristics of various PHBHHx films could not affect the metabolic activity of hMSCs, the performance of morphology of hMSCs was deeply affected by the hydrophilic nature and the orientation of surface scars. The hydrophilic nature would effectively improve the spread of hMSCs, and the orientation of surface scars would guide the growth direction of cytoskeleton (actin) inside hMSCs. In contrast, the behaviors of C3A/HepG2 hepatoma cells presented an opposite outcomes. Those surface characteristics were obviously associated with the performance of metabolic activity of C3A cells, but not with the morphology of C3A cells. Both hMSCs and C3A cells have unique cellular characteristics; therefore, their responses to environmental stimulations are significantly different.  相似文献   

9.
An injectable implant system that immediately forms a film around the injection site of an animal was successfully developed by dissolving microbial polyester poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) in not harmful organic solvents including N-methyl pyrrolidone (NMP), dimethylacetamide (DMAC), 1,4-dioxane (DIOX), dimethyl sulfoxide (DMSO) and 1,4-butanolide (BL), respectively. The formation of the PHBHHx film was the result of contact between aqueous body fluids and the amphiphilic PHBHHx solvents, leading to the controllable precipitation (film formation) of PHBHHx around the contact site. The resultant PHBHHx film assumed the shapes of its surrounding cavities. The resulting porous PHBHHx film was not favorable for attachment of Human Embryo Lung Fibroblast (HELF) cells. As a consequence, the fibroblasts cultured on the PHBHHx film exhibited a spheroid-like morphology. It was found that hydrophilicity of the PHBHHx film prepared using the above technique was significantly reduced compared with the poly(lactic acid) (PLA) film prepared for the same purpose and a PHBHHx film prepared from chloroform casting. This reduced hydrophilicity explains the poor attachment of fibroblast cells to the injectable PHBHHx film, suggesting that the PHBHHx injectable implant system can be developed as a tissue adhesion prevention film for surgical operations.  相似文献   

10.
The biocompatibility of microbial polyesters polyhydroxybutyrate (PHB) and poly(hydroxybutyrate-co-hydroxyhexanoate) (PHBHHx) were evaluated in vitro. The mouse fibroblast cell line L929 was inoculated on films made of PHB, PHBHHx and their blends, polylactic acid (PLA) as control. It was found that the growth of the cells L929 was poor on PHB and PLA films. The viable cell number ranged from 8.8 x 10(2) to 1.8 x 10(4)/cm2 only. Cell growth on the films made by blending PHB and PHBHHx showed a dramatic improvement. The viable cell number observed increased from 9.7 x 10(2) to 1.9 x 10(5) on a series of PHB/PHBHHx blended film in ratios of 0.9/0.1:0/1, respectively, indicating a much better biocompatibility in the blends contributed by PHBHHx. Biocompatibility was also strongly improved when these polymers were treated with lipases and NaOH, respectively. However, the effects of treatment were weakened when PHBHHx content increased in the blends. It was found that lipase treatment had more increased biocompatibility than NaOH. After the treatment biocompatibility of PHB was approximately the same as PLA, while PHBHHx and its dominant blends showed improved biocompatibility compared to PLA.  相似文献   

11.
Yang M  Zhu S  Chen Y  Chang Z  Chen G  Gong Y  Zhao N  Zhang X 《Biomaterials》2004,25(7-8):1365-1373
The objective of this study is to investigate the biocompatibility of poly (3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) with bone marrow stromal cells in vitro. The adsorption of fibronectin on the material was studied by enzyme-linked immunosorbent assay. After bone marrow stromal cells were seeded and cultured on PHBHHx, their proliferation was investigated by MTT. Differentiation of the cells was assessed by measuring alkaline phosphatase activity and by histochemical assay. The wettability and thermal property of PHBHHx films were also studied by contact angle goniometer, thermogravimetry and differential scanning calorimetry, respectively. The results show that bone marrow stromal cells can attach, proliferate and differentiate into osteoblasts on PHBHHx films. These results suggest that PHBHHx has good affinity with bone marrow stromal cells and may have potential applications in bone tissue engineering.  相似文献   

12.
Poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) was blended with poly(3-hydroxybutyrate-co-4-hydroxybutyrate) (P3HB4HB) to improve physical properties and biocompatibility of PHBHHx for a wide range of biomedical applications. PHBHHx was completely miscible with P3HB4HB in their blends. All the PHBHHx/P3HB4HB blends showed improved physical properties compared with PHBHHx, including higher thermal stability, flexibility and mechanical strength. All the blends had more hydrophilic surface, higher polar component and rougher surface than PHBHHx. The PHBHHx/P3HB4HB blend in 4:2 weight ratio showed the roughest surface and also had the highest chondrocyte viability among all the blends and the polymers tested, which was 59% higher than that on PHBHHx and 32% higher than that on P3HB4HB. The blend with 4:2 weight ratio also had the maximum cartilage-specific collagen II mRNA expression among all the blends and the polymers tested, which was 9-times higher than that on PHBHHx and 8-times higher than that on P3HB4HB. These results demonstrated that PHBHHx had improved physical properties and biocompatibility after blending with P3HB4HB. The blends could be used for cartilage tissue engineering.  相似文献   

13.
背景:可降解聚合材料3-羟基丁酸与3-羟基己酸共聚酯(3-hydroxybutyrate-co- 3-hydroxyhexanoate, PHBHHx)具有良好的机械性能和生物可降解性。 目的:在体研究PHBHHx的血管内生物相容性。 方法:采用脱细胞羊肺动脉为支架,以PHBHHx涂层,构建复合补片,植入新西兰兔腹主动脉内,以脱细胞未涂层羊肺动脉片作为对照。分别于植入后第1,4,12周取出移植补片进行组织学、免疫荧光染色、扫描电镜和钙含量测定。 结果与结论:复合补片管腔面光滑无血栓,内膜增生适度,再细胞化完全;免疫荧光染色可见新生内膜组织中类内皮细胞呈CD31阳性反应,单层连续排列,间质细胞呈平滑肌肌动蛋白阳性反应;复合补片的钙含量明显低于未涂层羊肺动脉片。说明PHBHHx的血管内生物相容性满意,是心血管组织工程较为理想的腔内涂层材料。  相似文献   

14.
As a new member of the polyhydroxyalkanoate (PHA) family, poly (3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) has better mechanical and processible properties than poly (3-hydroxybutyrate) (PHB). Still, it is difficult to introduce functional groups to the polyester carbon chain of PHBHHx, which restricts the modification of PHBHHx for a wide range. In this study, a procedure for the modification of the surface of PHBHHx films under strongly alkaline conditions was described. Through this kind of modification, carboxyl and hydroxyl groups were introduced to the surface and the total surface free energy was increased, which was mainly due to the increased polar components. Meanwhile, this process makes the surface rougher, resulting in larger total surface areas. After mineralization in simulated body fluids (SBFs), the apatite nucleation and growth on the surface-hydrolyzed PHBHHx films were significantly faster than on the unmodified PHBHHx films. This phenomenon should have a close relationship with the increased carboxyl and hydroxyl groups. The physicochemical properties also influenced the cell response to PHBHHx films. Compared to unmodified PHBHHx, fibronectin adsorption, and MC3T3-E1 cell attachment and proliferation were significantly greater on surface-hydrolyzed PHBHHx, which may be due to the increased surface free energy and rougher surface. Therefore, surface hydrolysis makes PHBHHx more suitable for osteoblast cell response and for application in bone-tissue engineering.  相似文献   

15.
Qu XH  Wu Q  Liang J  Zou B  Chen GQ 《Biomaterials》2006,27(15):2944-2950
In this paper, comprehensive characteristics including cell attachment, cell proliferation status, cell cycle progression and phenotypic changes of smooth muscle cells from rabbit aorta (RaSMCs) were studied on poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) containing 0-20% HHx (mol%) in comparison with tissue culture plates (TCPs). Results demonstrated that RaSMCs adhered better on PHBHHx containing 12% HHx (12%HHx) although they proliferated better on 20%HHx-containing PHBHHx films (20%HHx). This was explained by the difference in cell cycle progression observed using flow cytometry, as it was found that only 20%HHx-containing polymer could maintain the normal cell cycle evolution as TCPs did after 3 d incubation. The highest expression level and typical spindle-like distribution of alpha-actin on 20%HHx-containing polymer were characterized as the contractile-like phenotype, suggesting that RaSMCs tended to differentiate rather than proliferate compared to the cells grown on 12%HHx polymer. Results obtained above suggested that 20%HHx was suitable for RaSMCs proliferation, leading to its change to contractile phenotype. This study extends the potential applications of PHBHHx in SMCs-related graft scaffold fabrication for tissue engineering.  相似文献   

16.
A series of composite films of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) modified with polyvinylpyrrolidone (PVP) was prepared by varying the ratio of constituents, and their properties and cytocompatibility were evaluated. The hydrophilicity of the blended materials surfaces increased and the amounts of fibronectin and laminin adsorbed on the materials surface increased remarkably compared with PHBHHx. FT-IR spectra of the blended films showed a new band, implying that a surface physical interpenetrating network structure had formed. Scanning electron microscopy showed that there were dense pits and holes on the blended films surface. For the films of PHBHHx with 20 wt% and 40 wt% PVP, MTT assay indicated that PVP enhanced cell adhesion and proliferation, but that the effects were impaired by excessive PVP. The results suggested that proper addition of PVP increased the cytocompatibility of PHBHHx because the material surface had increased hydrophilicity and presented an appropriate morphology.  相似文献   

17.
A series of composite films of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) modified with polyvinylpyrrolidone (PVP) was prepared by varying the ratio of constituents, and their properties and cytocompatibility were evaluated. The hydrophilicity of the blended materials surfaces increased and the amounts of fibronectin and laminin adsorbed on the materials surface increased remarkably compared with PHBHHx. FT-IR spectra of the blended films showed a new band, implying that a surface physical interpenetrating network structure had formed. Scanning electron microscopy showed that there were dense pits and holes on the blended films surface. For the films of PHBHHx with 20 wt% and 40 wt% PVP, MTT assay indicated that PVP enhanced cell adhesion and proliferation, but that the effects were impaired by excessive PVP. The results suggested that proper addition of PVP increased the cytocompatibility of PHBHHx because the material surface had increased hydrophilicity and presented an appropriate morphology.  相似文献   

18.
Qu XH  Wu Q  Zhang KY  Chen GQ 《Biomaterials》2006,27(19):3540-3548
The in vivo tissue reactions and biodegradations of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx), poly(lactide) (PLA), poly(3-hydroxybutyrate) (PHB), blends of PHBHHx (X) and poly(ethylene glycol) (PEG) (E) with ratios of 1:1 (E1X1) and 1:5 (E1X5), respectively, were evaluated by subcutaneous implantation in rabbits. Results revealed that the degradation rate increased in the order of PHB < PHBHHx < PLA. During the implantation period, crystallinity of PHBHHx increased from 19% to 22% and then dropped to 14%. Gel permeation chromatography (GPC) displayed increasing polydispersity and typical bimodal distribution from 3 to 6 months. The above results suggested that rapid PHBHHx degradation occurred in amorphous region rather than in crystalline region. While the in vivo hydrolysis of PHB was found to start from a random chain scission both in amorphous and crystalline regions of the polymer matrix, as demonstrated by its hydrolysis process accompanied by a decrease in molecular weight with unimodal distribution and relatively narrow polydispersity. Compared to pure PHBHHx, PHBHHx-PEG blends showed accelerated weight loss of PHBHHx with weak molecular weight reduction. In general, PHBHHx elicited a very mild tissue response during implantation lasting 6 months compared with relative acute immunological reactions observed among PHB and PLA objects, respectively. Pronounced tissue responses were observed in the capsule surrounding E1X1 and E1X5 as characterized by the presence of lymphocytes, eosinophils and vascularization, which might be resulted from the continuous leaching of PEG.  相似文献   

19.
Li XT  Zhang Y  Chen GQ 《Biomaterials》2008,29(27):3720-3728
Polyhydroxyalkanoates (PHAs) have been demonstrated to be a family of biopolymers with good biodegradability and biocompatibility. To mimic the real microenvironment of extracellular matrix (ECM) for cell growth, novel nanofiber matrices based on PHA polymers were prepared via a phase separation process. Three-dimensional interconnected fibrous networks were observed in these matrices with average fiber diameters of 50-500 nm, which are very similar to the major ECM component collagen. Compared with nanofiber matrix made of poly(L-lactide), the mechanical properties of PHA nanofiber matrices were significantly improved, especially those matrices of PHA blends PHB/PHBHHx containing polyhydroxybutyrate (PHB) and copolyesters PHBHHx consisting of 3-hydroxybutyrate and 3-hydroxyhexanoate, and PHB/P3HB4HB that are PHB blended with copolyesters of 3-hydroxybutyrate and 4-hydroxybutyrate, respectively. More importantly, cell attachment and growth of human keratinocyte cell line HaCat on the nanofiber PHA matrices showed a notable improvement over those on PHA matrices prepared via an ordinary solution casting method. It was therefore proposed that PHA nanofiber matrices combined the advantages of biodegradation, improved mechanical strengths and the nanostructure of a natural extracellular matrix, leading to a better cell compatibility, thus they can be used for future implant biomaterial development.  相似文献   

20.
背景:与聚乳酸、聚羟基乙酸和乳酸-羟基乙酸共聚物等生物材料相比,3-羟基丁酸和3-羟基己酸共聚酯结构多元化,具有更好的生物相容性能、生物可降解性和热加工性能。 目的:采用细胞培养法评估含不同质量浓度阿魏酸的3-羟基丁酸和3-羟基己酸共聚酯涂层的生物相容性。 方法:室温下使用乙酸乙酯配制含0(对照组),50,100,130,150 g/L阿魏酸的3-羟基丁酸和3-羟基己酸共聚酯,观察成膜外观。通过MTT吸光度检测、荧光显微镜观察以及扫描电镜观察方法对比评估骨髓间充质干细胞在其表面的生长状态。 结果与结论:含50 g/L阿魏酸的3-羟基丁酸和3-羟基己酸共聚酯成膜后外观均匀半透明,未见白色结晶析出物,含100,130,150 g/L阿魏酸的3-羟基丁酸和3-羟基己酸共聚酯在成膜后均出现点状白色结晶物。MTT吸光度检测表明含50,100 g/L阿魏酸的3-羟基丁酸和3-羟基己酸共聚酯均能较好地促进骨髓间充质干细胞生长;荧光显微镜及扫描电镜观察均见骨髓间充质干细胞能够在含50,100 g/L阿魏酸的3-羟基丁酸和3-羟基己酸共聚酯表面黏附生长。说明含50 g/L阿魏酸的3-羟基丁酸和3-羟基己酸共聚酯最适合作为镁合金的涂层材料。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号