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1.
This paper reports the effect of the combined technique of dehydrothermal treatment (DHT) and a mixture of 1‐ethyl‐3(3‐dimethylaminopropyl) carbodiimide (EDC) and N‐hydroxysuccinimide (NHS) crosslinking on the physicochemical properties of collagen/hydroxyapatite materials. Collagen and collagen/hydroxyapatite porous scaffolds containing different amounts of collagen and hydroxyapatite were prepared with use of the freeze‐drying technique. All samples were capable of absorbing a large quantity of phosphate buffered saline. Samples crosslinked by DHT+EDC/NHS presented higher resistance to collagenase degradation (with slightly reduced degradation in DHT+EDC/NHS crosslinked scaffolds prepared from 2% collagen solution), whereas DHT scaffolds exhibited faster degradation. Mechanical testing results suggested that scaffolds crosslinked by DHT+EDC/NHS treatment have an improved compressive modulus compared with EDC/NHS crosslinking. The qualitative analysis of colour intensity resulting from the CellTiter 96 Aqueous One Solution Cell Proliferation Assay (MTS) led to the conclusion that all samples, regardless of the crosslinking method, were well tolerated by cells. However, DHT and EDC/NHS crosslinked scaffolds seem to support better cell viability, in contrast to DHT+EDC/NHS crosslinked scaffolds that support cell differentiation instead. DHT+EDC/NHS crosslinked scaffolds markedly increase the specific alkaline phosphatase activity of cells, which may be of benefit in bone tissue engineering. © 2017 Society of Chemical Industry  相似文献   

2.
A novel composite hydrogel based on gelatin, sodium alginate (SA) and hyaluronic acid (HYA) was fabricated by freeze-drying method using 1-ethyl-(3-3-dimethylaminopropyl) carbodiimide (EDC) as a cross-linker. The effects of chemical cross-linking, including cross-linker content and cross-linking time, on the morphology, swelling ratio and compressive strength of the gelatin/SA/HYA hydrogel were investigated. The influence of pH value of the swelling medium on the swelling ratio of the gelatin/SA/HYA composite hydrogel was also studied. The results showed that the gelatin/SA/HYA composite hydrogel had a three-dimensional interconnected structure and the pore size decreased with increasing EDC concentration. The IR absorption peak intensity of the gelatin/SA/HYA hydrogel has no obvious variety with increasing EDC content. The swelling ratio of the gelatin/SA/HYA hydrogel decreased with increasing cross-linker content and cross-linking time; however, the compressive strength increased with increasing EDC content and cross-linking time. The hydrogel swelling peak reached at pH 7. Therefore, the architecture and the physical properties of the gelatin/SA/HYA composite hydrogel can be adjusted by controlling the chemical cross-linking conditions and pH value of swelling medium.  相似文献   

3.
Compared with traditional conjugates 1-ethyl-3-(3-dimethyl aminopropyl) carbodiimide (EDC) and N-hydroxysuccinimide (NHS), 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride (DMTMM) is an emerging biological coupling reagent and has been used in the amidation of hyaluronic acid. In this paper, DMTMM was used to achieve the amidation of chitosan (CS) with glucuronic acid (GA) in an aqueous medium to generate a GA-CS derivative. The grafting efficacy was preliminarily compared with the EDC/NHS-mediated reaction. As a result, the substitution degree of 17.6% for DMTMM-mediated grafting and 13.1% for EDC/NHS chemistry indicated that DMTMM-mediated synthesis of GA-CS appeared to be more efficient. The reaction kinetics experiments showed that GA-CS derivative with a degree of substitution up to about 26.1% was obtained using equal molar ratios of DMTMM and GA exceeding CS at room temperature. These results indicate that employing DMTMM as a coupling agent is a feasible and promising strategy for the amidation modification of chitosan.  相似文献   

4.
Gelatin has excellent biological properties, but its poor physical properties are a major obstacle to its use as a biomaterial ink. These disadvantages not only worsen the printability of gelatin biomaterial ink, but also reduce the dimensional stability of its 3D scaffolds and limit its application in the tissue engineering field. Herein, biodegradable suture fibers were added into a gelatin biomaterial ink to improve the printability, mechanical strength, and dimensional stability of the 3D printed scaffolds. The suture fiber reinforced gelatin 3D scaffolds were fabricated using the thermo-responsive properties of gelatin under optimized 3D printing conditions (−10 °C cryogenic plate, 40–80 kPa pneumatic pressure, and 9 mm/s printing speed), and were crosslinked using EDC/NHS to maintain their 3D structures. Scanning electron microscopy images revealed that the morphologies of the 3D printed scaffolds maintained their 3D structure after crosslinking. The addition of 0.5% (w/v) of suture fibers increased the printing accuracy of the 3D printed scaffolds to 97%. The suture fibers also increased the mechanical strength of the 3D printed scaffolds by up to 6-fold, and the degradation rate could be controlled by the suture fiber content. In in vitro cell studies, DNA assay results showed that human dermal fibroblasts’ proliferation rate of a 3D printed scaffold containing 0.5% suture fiber was 10% higher than that of a 3D printed scaffold without suture fibers after 14 days of culture. Interestingly, the supplement of suture fibers into gelatin biomaterial ink was able to minimize the cell-mediated contraction of the cell cultured 3D scaffolds over the cell culture period. These results show that advanced biomaterial inks can be developed by supplementing biodegradable fibers to improve the poor physical properties of natural polymer-based biomaterial inks.  相似文献   

5.
The present study delineates the development of chitosan and poly(L-lactide) (PLLA) scaffolds cross-linked using a mixture of 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC), n-hydroxysuccinimide (NHS), and chondroitin sulfate (CS) for cartilage tissue engineering applications. Chitosan and PLLA were varied in concentration for developing scaffolds and prepared by freeze-drying method. The various scaffolds were studied using scanning electron microscopy (SEM), porosity by mercury intrusion porosimeter, and the molecular interactions among polymers using Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) studies. Differential scanning calorimetry was used to predict the thermal properties of the scaffolds. The mechanical properties of the scaffolds were studied using static mechanical tester. The ability of the scaffolds to support chondrocyte proliferation was also studied. The microscopy suggests that the pore size of the scaffolds varied with the composition in the range of 38–172 μm and the porosities in the range of 73–93%. The XRD and the FTIR studies suggested that an alternation in the composition of the scaffolds altered the molecular interactions among the scaffold components. An increase in the chitosan content enhanced the swelling property. The degradation of the scaffolds was least when the proportion of chitosan and PLLA was in the ratio of 70:30. The in vitro cell proliferation study suggested that the developed scaffolds were able to support chondrogenesis, the glycosaminoglycan (GAG) content of the mature chondrocyte was 40 μg/ml and the viability was approximately 90%. Hence, the so designed scaffolds may be tried for cartilage tissue engineering applications.  相似文献   

6.
Scaffold‐guided tissue engineering based on synthetic and natural occurring polymers has gained many interests in recent year. In this study, the development of a chitosan‐heparin artificial extracellular matrix (AECM) is reported. Three‐dimensional, macroporous composite AECMs composed of heparin (Hep) and chitosan (Chito) were prepared by an interpolyelectrolyte complex/lyophilization method. The Chito‐Hep composite AECMs were, respectively, crosslinked with glutaraldehyde, as well as cocrosslinked with N,N‐(3‐dimethylaminopropyl)‐N′‐ethyl carbodiimide (EDC/NHS) and N‐hydroxysuccinimide (NHS). The crosslinking reactions were examined by FT‐IR analysis. In physiological buffer solution (PBS), the EDC/NHS‐crosslinked Chito‐Hep composite AECM showed a relative lower water retention ratio than its glutaraldehyde‐crosslinked counterparts. The EDC/NHS‐crosslinked Chito‐Hep composite AECMs showed excellent biocompatibility, according to the results of the in vitro cytotoxic test. This result suggested that the EDC/NHS‐crosslinked Chito‐Hep composite AECMs might be a potential biomaterial for scaffold‐guided tissue engineering applications. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   

7.
Summary: Biomimetic scaffolds are appealing products for the repair of bone defects using tissue engineering strategies. The present study prepared novel biomimetic composite scaffolds with similar composite to natural bone using bioactive glass, collagen, hyaluronic acid, and phosphatidylserine. The microstructure, swelling ratio, biodegradability, and biomineralization characteristic of the composite scaffolds with and without hyaluronic acid and phosphatidylserine were compared and analyzed by SEM/EDAX, XRD, and FTIR techniques and in vitro test, and the properties can be influenced by 1‐ethyl‐3‐(3‐dimethylaminopropyl) carbodiimide (EDC)/N‐hydroxysuccinimide (NHS) crosslinking. The optimized properties of the crosslinked composite scaffolds observed in this study show the possibility of their use of bioactive and bioresorbable scaffolds in bone tissue engineering.

SEM micrographs of BG‐COL‐HYA‐PS composite scaffolds after immersion in SBF for 1 d.  相似文献   


8.
A novel biocompatible scaffold was prepared by cross‐linking hyaluronan (HA) and chitosan (CS). The carboxyl groups of HA were activated by 1‐ethyl‐3‐(3‐dimethylaminopropyl)carbodiimide (EDC) and then cross‐linked with amino groups of CS by forming amide bonds. The HA/CS scaffold thus prepared was characterized using Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM) and differential scanning calorimetry. FTIR spectra showed that the absorbance of the amide (1550 cm?1) and carbonyl (1633 cm?1) bond in the cross‐linked scaffold was stronger than that in HA or CS. SEM micrographs showed that the cross‐linked scaffold produced at low EDC concentration had an intertwisted ribbon‐like microstructure, while the product prepared at higher EDC concentration had a porous structure. The concentration of EDC in the reaction system greatly affected the structure and properties of the HA/CS scaffold. The prepared scaffold could strongly resist degradation by hyaluronidase, free radicals in vitro and stress. Copyright © 2007 Society of Chemical Industry  相似文献   

9.
Aligned nanofibrous blends of poly (d, l-lactide-co-glycolide) (PLGA) and collagen with various PLGA/collagen compositions (80/20, 65/35 and 50/50) were fabricated by electrospinning and characterized for bone tissue engineering. Morphological characterization showed that the addition of collagen to PLGA resulted in narrowing of the diameter distribution and a reduction in average diameter. Differential scanning calorimetric (DSC) studies showed that the triple helix structure of the native collagen was not destroyed during the fabrication process. However, the blending had a marked effect on the overall enthalpy of the blends, whereby the total enthalpy decreased as the collagen content decreased. Thermogravimetric analysis showed the addition of collagen increased the hydrophilicity of the scaffolds. The crosslinking of collagen to increase the biostability was done using 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC) in ethanol and an overall ∼25% degree of crosslinking was achieved. The EDC crosslinking had little effect on the nanofibrous morphology of the 80/20 blend system; however, the nanofibrous features were compromised to some extent at higher collagen concentrations. The mechanical characterization under dry and wet conditions showed that increasing collagen content resulted in a tremendous decrease in the mechanical properties. However, crosslinking resulted in the increase in elastic modulus from 47 MPa to 83 MPa for the wet PLGA/Collagen 80/20 blend system, with little effect on the tensile strength. In conclusion, the aligned nanofibrous scaffold used in this study constitutes a promising material for bone tissue engineering.  相似文献   

10.
In this study, a novel freeze‐gelation method instead of the conventional freeze‐drying method was used to fabricate porous chitosan/collagen‐based composite scaffolds for skin‐related tissue engineering applications. To improve the performance of chitosan/collagen composite scaffolds, we added 1‐ethyl‐3‐(3‐dimethylaminopropyl)‐carbodiimide (EDC) and amino acids (including alanine, glycine, and glutamic acid) in the fabrication procedure of the composite scaffolds, in which amino acid molecules act as crosslinking bridges to enhance the EDC‐mediated crosslinking. This novel combination enhanced the tensile strength of the scaffolds from 0.70 N/g for uncrosslinked scaffolds to 2.2 N/g for crosslinked ones; the crosslinked scaffolds also exhibited slower degradation rates. The hydrophilicity of the scaffolds was also significantly enhanced by the addition of amino acids to the scaffolds. Cell compatibility was demonstrated by the in vitro culture of human skin fibroblasts on the scaffolds. The fibroblasts attached and proliferated well on the chitosan/collagen composite scaffolds, especially the one with glutamic acid molecules as crosslinking bridges, whereas cells did not grow on the chitosan scaffolds. Our results suggest that the collagen‐modified chitosan scaffolds with glutamic acid molecules as crosslinking bridges are very promising biomaterials for skin‐related tissue engineering applications because of their enhanced tensile strength and improved cell compatibility with skin fibroblasts. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007  相似文献   

11.
In the fast-developing field of tissue engineering there is a constant demand for new materials as scaffolds for cell seeding, which can better mimic a natural extracellular matrix as well as control cell behavior. Among other materials, polysaccharides are widely used for this purpose. One of the main candidates for scaffold fabrication is alginate. However, it lacks sites for cell adhesion. That is why one of the steps toward the development of suitable scaffolds for cells is the introduction of the biofunctionality to the alginate structure. In this work we focused on bone-sialoprotein derived peptide (TYRAY) conjugation to the molecule of alginate. Here the comparison study on four different approaches of peptide conjugation was performed including traditional and novel modification methods, based on 1-Ethyl-3-(3-dimethylaminopropyl)carbodiimide/N-hydroxy succinimide (EDC/NHS), 4-(4,6-dimethoxy-1,3,5-triazine-2-yl)-4-methylmorpholinium chloride (DMTMM), thiol-Michael addition and Cu-catalyzed azide–alkyne cycloaddition reactions. It was shown that the combination of the alginate amidation with the use of and subsequent Cu-catalyzed azide–alkyne cycloaddition led to efficient peptide conjugation, which was proven with both NMR and XPS methods. Moreover, the cell culture experiment proved the positive effect of peptide presence on the adhesion of human embryonic stem cells.  相似文献   

12.
To improve the properties of chitosan (CS) and poly(L‐lactic acid) (PLLA) and obtain fully biodegradable materials, CS‐g‐PLLA copolymers were prepared using 1‐(3‐Dimethylaminopropyl)‐3‐ethylcarbodiimide hydrochloride (EDC)/N‐hydroxyl succinimide (NHS) as a coupling agent. The copolymers were characterized by Fourier transform infrared analysis (FTIR), 1H nuclear magnetic resonance (1H NMR), elemental analysis, differential scanning calorimetry (DSC), X‐ray diffraction (XRD) and scanning electron microscopy (SEM). The results obtained by FTIR and 1H NMR showed that CS and PLLA were grafted successfully via an amide bond. DSC and XRD results showed that the thermal stability of CS had been significantly improved by grafting PLLA to the molecular chains of CS and the crystallinity of the CS‐g‐PLLA copolymers decreased significantly. Elemental analysis showed that the achieved the maximum degree of substitution of PLLA was 60.88%, while the concentration of CS was 2 mg/mL, the PLLA molecular weight was 10,000, and the EDC/NHS ratio was 2:1. Images from SEM demonstrated that the copolymers had a spherical shape and smooth surface. Moreover, the products were well dispersed without any aggregation. POLYM. ENG. SCI., 56:1432–1436, 2016. © 2016 Society of Plastics Engineers  相似文献   

13.
Scaffold‐guided tissue engineering based on synthetic and natural occurring polymers has gained much interest in recent years. In this article, the development of a polysaccharide‐based artificial extracellular matrix (AECM) is reported. Three‐dimensional, macroporous composite AECMs composed of chondroitin sulfate (ChS) and chitosan (Chito) were prepared by an interpolyelectrolyte complex/lyophilization method. The ChS–Chito composite AECMs were crosslinked with glutaraldehyde and calcium ions (Ca2+) and cocrosslinked with N,N‐(3‐dimethylaminopropyl)‐N′‐ethyl carbodiimide (EDC) and N‐hydroxysuccinimide (NHS). The crosslinking reactions were examined with Fourier transform infrared analysis. Glutaraldehyde and Ca2+ crosslinked with Chito and ChS, respectively, to produce different types of ChS–Chito semi‐interpenetrated networks. In contrast, EDC/NHS crosslinked with both Chito and ChS to produce ChS–Chito connected networks. In physiological buffer solutions, the Ca2+‐crosslinked ChS–Chito composite AECMs showed a lower swelling ratio than their EDC/NHS‐ and glutaraldehyde‐crosslinked counterparts. The ChS–Chito composite AECMs showed excellent antibacterial capability and biocompatibility according to the results of the in vitro antibacterial test and cytotoxic assay. This result suggested that the ChS–Chito composite AECMs might be a potential biomaterial for scaffold‐guided tissue‐engineering applications. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci, 2006  相似文献   

14.
The porous scaffold of nanobiphasic calcium phosphate (n-BCP) and gelatin from bovine skin type B was prepared by freeze-drying method. The porogen which used was Naphthalene. EDC (N-(3-dimethyl aminopropyl)-N′-ethyl carbodiimide hydrochloride) for stabilization of gelatin by cross-linking method was used. The scaffold was characterized by SEM, XRD and FTIR. As a result, a biocompatible scaffold with good cell attachment, facility in formation in desired shapes and simplicity in production were prepared for bone tissue engineering.  相似文献   

15.
In this study, a novel composite hydrogel with improved cellular structure and mechanical properties was prepared by the crosslinking of hyaluronic acid (HA) and sodium alginate (SAL). The amide linkages (covalent bonds) in the hydrogel that we expected to form were confirmed by Fourier transform infrared spectroscopy. The hydrogels had a pore size larger than 100 μm and were observed by scanning electron microscopy. Texture profile analysis indicated that the hardness of the hydrogels was enhanced by an increase in the polymer's concentration, but it declined with an increase in the HA/SAL molar ratio. The swelling capacity was reduced with increases in the polymer's concentration and the 1‐ethyl‐3‐(3‐dimethyl aminopropyl)‐1‐carbodiimide hydrochloride (EDC)/HA molar ratio, and it was enhanced by an increase in the HA/SAL molar ratio. The resistance against hyaluronidase was negatively correlated with the proportion of HA in the hydrogels and positively correlated with the EDC/HA molar ratio. Given the improved physicochemical properties that we produced, these novel hydrogels may have the potential to be applied in tissue engineering scaffolding. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41898.  相似文献   

16.
Two artificial intelligence techniques, namely artificial neural network (ANN) and genetic algorithm (GA) were combined to be used as a tool for optimizing the covalent immobilization of cellulase on a smart polymer, Eudragit L-100. 1-Ethyl-3-(3-dimethyllaminopropyl) carbodiimide (EDC) concentration, N-hydroxysuccinimide (NHS) concentration and coupling time were taken as independent variables, and immobilization efficiency was taken as the response. The data of the central composite design were used to train ANN by back-propagation algorithm, and the result showed that the trained ANN fitted the data accurately (correlation coefficient R(2) = 0.99). Then a maximum immobilization efficiency of 88.76% was searched by genetic algorithm at a EDC concentration of 0.44%, NHS concentration of 0.37% and a coupling time of 2.22 h, where the experimental value was 87.97 ± 6.45%. The application of ANN based optimization by GA is quite successful.  相似文献   

17.
以明胶(Gel)、壳聚糖(CS)、纳米纤维素(NCC)为原料,采用溶液共混法制备了不同NCC和CS质量比的纳米纤维素/壳聚糖/明胶复合膜。采用紫外-可见分光光度计、扫描电镜(SEM)、红外光谱仪(FT-IR)、X射线衍射仪(XRD)、热分析仪(TGA)和质构仪对所制备复合膜的透光性能、显微结构、化学结构、晶体结构、热学性能和力学性能进行了分析。结果表明:纳米纤维素、壳聚糖、明胶之间形成相互作用较强的网络结构。复合膜表面光滑,分散均匀,具有良好的相容性。随着纳米纤维素含量的增加,复合膜透光率呈下降的趋势。与壳聚糖膜相比,复合膜的热稳定性显著提高。当纳米纤维素与壳聚糖质量比为7:1时,复合膜拉伸强度最高可达到33 MPa,断裂伸长率可达到14.9%,吸水率最大值可达到341%。  相似文献   

18.
Hyaluronic acid (HA) ultra-thin fibrous membranes by electrospinning technology had been fabricated successfully by our group. However, these HA fibrous membranes dissolve and decompose rapidly in water. In this study, chemical crosslinking of HA and HA based ultra-thin fibrous membranes was studied in detail. It was found that the chemically crosslinked pure HA ultra-thin fibrous membranes with 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC) as the crosslinking agent did not show an obvious improvement in the water-resistance. However, by simply adding and changing the gelatin content, the degradation time of the HA based fibrous membranes could be effectively adjusted from one week to several months. That is with the increase in gelatin content, the water-resistance of the HA/gelatin bi-component membranes could be increased greatly. The crosslinked HA/gelatin bi-component membranes were evaluated in vitro by seeding with mouse embryonic fibroblasts (3T6-Swiss Albino). The results showed that the HA/gelatin fibrous membranes were cytocompatible and suitable for cell viability. However, cells were hard to attach and grow on the HA based membranes. Thus, the HA/gelatin fibrous membranes with controllable degradation rate could have good potential applications in the anti-adhesion and wound dressing fields.  相似文献   

19.
The vision impairments suffered by millions of people worldwide and the shortage of corneal donors show the need of substitutes that mimic native tissue to promote cell growth and subsequent tissue regeneration. The current study focused on the in vitro assessment of protein-based biomaterials that could be a potential source for corneal scaffolds. Collagen, soy protein isolate (SPI), and gelatin films cross-linked with lactose or citric acid were prepared and physicochemical, transmittance, and degradation measurements were carried out. In vitro cytotoxicity, cell adhesion, and migration studies were performed with human corneal epithelial (HCE) cells and 3T3 fibroblasts for the films’ cytocompatibility assessment. Transmittance values met the cornea’s needs, and the degradation profile revealed a progressive biomaterials’ decomposition in enzymatic and hydrolytic assays. Cell viability at 72 h was above 70% when exposed to SPI and gelatin films. Live/dead assays and scanning electron microscopy (SEM) analysis demonstrated the adhesion of both cell types to the films, with a similar arrangement to that observed in controls. Besides, both cell lines were able to proliferate and migrate over the films. Without ruling out any material, the appropriate optical and biological properties shown by lactose-crosslinked gelatin film highlight its potential for corneal bioengineering.  相似文献   

20.
《Ceramics International》2019,45(12):14608-14613
We investigated the bioactivity and cytocompatibility of 45S5 bioactive glass (BG) based scaffolds coated with a composite layer formed by gelatin and manganese doped mesoporous bioactive glass nanoparticles (Mn-MBGNs). The scaffolds were prepared using the foam replica method, and they were further coated with Mn-MBGNs/gelatin via dip coating. The synthesized scaffolds were characterized in relation to morphology, porosity, mechanical stability, bioactivity and cell biology behavior using osteoblast-like (MG-63) cells. The scaffolds were highly porous with interconnected porosity, and a suitable pore structure was maintained even after the Mn-MBGNs/gelatin coating. Energy-dispersive X-ray spectroscopy (EDX) confirmed the presence of Mn-MBGNs in the coatings. Moreover, the presence of gelatin was confirmed by Fourier transform infrared spectroscopy (FTIR). The coated scaffolds exhibited in-vitro bioactivity in simulated body fluid comparable to that of uncoated BG scaffolds. Finally, Mn-MBGNs/gelatin coated scaffolds were shown to be non-cytotoxic to MG-63 cells. Hence, the results presented here confirm that the novel Mn containing scaffolds can be considered in the field of biologically active ion releasing scaffolds for bone tissue engineering applications.  相似文献   

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