AIM: To facilitate engineering of suitable biomaterials to meet the challenges associated with myocardial infarction. METHODS: Poly (glycerol sebacate)/collagen (PGS/ collagen) core/shell fibers were fabricated by cor...AIM: To facilitate engineering of suitable biomaterials to meet the challenges associated with myocardial infarction. METHODS: Poly (glycerol sebacate)/collagen (PGS/ collagen) core/shell fibers were fabricated by core/ shell electrospinning technique, with core as PGS and shell as collagen polymer; and the scaffolds were characterized by scanning electron microscope (SEM), fourier transform infrared spectroscopy (FTIR), contact angle and tensile testing for cardiac tissue engineering. Collagen nanofibers were also fabricated by electrospinning for comparison with core/shell fibers. Studies on cell-scaffold interaction were carriedout using cardiac cells and mesenchymal stem cells (MSCs) co-culture system with cardiac cells and MSCs separately serving as positive and negative controls respectively. The co-culture system was characterized for cell proliferation and differentiation of MSCs into cardiomyogenic lineage in the co-culture environment using dual immunocytochemistry. The co-culture cells were stained with cardiac specific marker proteins like actinin and troponin and MSC specific marker protein CD 105 for proving the cardiogenic differentiation of MSCs. Further the morphology of cells was analyzed using SEM.RESULTS: PGS/collagen core/shell fibers, core is PGS polymer having an elastic modulus related to that of cardiac fibers and shell as collagen, providing natural environment for cellular activities like cell adhesion, proliferation and differentiation. SEM micrographs of electrospun fibrous scaffolds revealed porous, beadless, uniform fibers with a fiber diameter in the range of 380 ± 77 nm and 1192 ± 277 nm for collagen fibers and PGS/collagen core/shell fibers respectively. The obtained PGS/collagen core/shell fibrous scaffolds were hydrophilic having a water contact angle of 17.9 ± 4.6° compared to collagen nanofibers which had a contact angle value of 30 ± 3.2°. The PGS/collagen core/shell fibers had mechanical properties comparable to that of native heart muscle with a young's modulus of 4.24 ± 0.7 MPa, while that of collagen nanofibers was comparatively higher around 30.11 ± 1.68 MPa. FTIR spectrum was performed to confirm the functional groups present in the electrospun scaffolds. Amide Ⅰ and amide Ⅱ of collagen were detected at 1638.95 cm -1 and 1551.64 cm -1 in the electrospun collagen fibers and at 1646.22 cm -1 and 1540.73 cm -1 for PGS/collagen core/shell fibers respectively. Cell culture studies performed using MSCs and cardiac cells co-culture environment, indicated that the cellproliferation significantly increased on PGS/collagen core/shell scaffolds compared to collagen fibers and the cardiac marker proteins actinin and troponin were expressed more on PGS/collagen core/shell scaffolds compared to collagen fibers alone. Dual immunofluorescent staining was performed to further confirm the cardiogenic differentiation of MSCs by employing MSC specific marker protein, CD 105 and cardiac specific marker protein, actinin. SEM observations of cardiac cells showed normal morphology on PGS/collagen fibers and providing adequate tensile strength for the regeneration of myocardial infarction. CONCLUSION: Combination of PGS/collagen fibers and cardiac cells/MSCs co-culture system providing natural microenvironments to improve cell survival and differentiation, could bring cardiac tissue engineering to clinical application.展开更多
Because of the inherent appearance similar to the natural extracellular matrix,ultrafine fibrous membranes prepared via electrospinning exhibit widespread applications,especially in the biomedical area.Extensional mod...Because of the inherent appearance similar to the natural extracellular matrix,ultrafine fibrous membranes prepared via electrospinning exhibit widespread applications,especially in the biomedical area.Extensional modifications of coaxial and emulsion electrospinning have drawn much attention in preparation of core/shell fibers for applications as tissue engineering scaffolds and controlled delivery systems for bioactive substances.Due to incorporation of multi-components in the electrospun core/ shell fibers,the process of coaxial and emulsion electrospinning became more susceptible.The theories have not been fully understood.A series of investigations were carried out evaluating the systematic and processing parameters.This paper reviews advantages and potentials of electrospun core/shell fibers as well as factors influencing their formation on the basis of our research and new progress.展开更多
Polystyrene(PS) fibers with core-shell structures were fabricated by coaxial electrostatic spinning,[10_TD$IF]in which there are liquid epoxy or curing agent as the core and PS as the shell. Scanning electron microsco...Polystyrene(PS) fibers with core-shell structures were fabricated by coaxial electrostatic spinning,[10_TD$IF]in which there are liquid epoxy or curing agent as the core and PS as the shell. Scanning electron microscopy(SEM), Fourier transform infrared(FTIR) spectra and optical microscope were utilized for charactering the morphology and composition of the fibers. Composite coatings embedded with the healant-loaded coreshell fibers have been prepared and the self-healing of the scratch on the coatings has been revealed.展开更多
采用同轴静电纺丝技术制备聚乳酸(PLA)-聚己内酯(PCL)核-壳结构复合纤维.利用扫描电子显微镜(SEM)观察纺丝电压、收集距离和核层-壳层溶液推进速度对PLA-PCL核-壳结构复合纤维形貌的影响.通过透射扫描电子显微镜(TEM)分析核层-壳层溶液...采用同轴静电纺丝技术制备聚乳酸(PLA)-聚己内酯(PCL)核-壳结构复合纤维.利用扫描电子显微镜(SEM)观察纺丝电压、收集距离和核层-壳层溶液推进速度对PLA-PCL核-壳结构复合纤维形貌的影响.通过透射扫描电子显微镜(TEM)分析核层-壳层溶液推进速度对PLA-PCL核-壳结构形成的影响.研究结果表明:当核-壳溶液推进速度为0.1-0.2和0.1-0.3 m L/h时形成了清晰的核-壳结构;随着壳层溶液推进速度加快,PLA-PCL复合纤维核层含量降低,增加纺丝电压能够有效地降低复合纤维平均直径,而增大收集距离使复合纤维平均直径先降低后增加.展开更多
基金Supported by NRF-Technion, No. R-398-001-065-592Ministry of Education, No. R-265-000-318-112NUSNNI, National University of Singapore
文摘AIM: To facilitate engineering of suitable biomaterials to meet the challenges associated with myocardial infarction. METHODS: Poly (glycerol sebacate)/collagen (PGS/ collagen) core/shell fibers were fabricated by core/ shell electrospinning technique, with core as PGS and shell as collagen polymer; and the scaffolds were characterized by scanning electron microscope (SEM), fourier transform infrared spectroscopy (FTIR), contact angle and tensile testing for cardiac tissue engineering. Collagen nanofibers were also fabricated by electrospinning for comparison with core/shell fibers. Studies on cell-scaffold interaction were carriedout using cardiac cells and mesenchymal stem cells (MSCs) co-culture system with cardiac cells and MSCs separately serving as positive and negative controls respectively. The co-culture system was characterized for cell proliferation and differentiation of MSCs into cardiomyogenic lineage in the co-culture environment using dual immunocytochemistry. The co-culture cells were stained with cardiac specific marker proteins like actinin and troponin and MSC specific marker protein CD 105 for proving the cardiogenic differentiation of MSCs. Further the morphology of cells was analyzed using SEM.RESULTS: PGS/collagen core/shell fibers, core is PGS polymer having an elastic modulus related to that of cardiac fibers and shell as collagen, providing natural environment for cellular activities like cell adhesion, proliferation and differentiation. SEM micrographs of electrospun fibrous scaffolds revealed porous, beadless, uniform fibers with a fiber diameter in the range of 380 ± 77 nm and 1192 ± 277 nm for collagen fibers and PGS/collagen core/shell fibers respectively. The obtained PGS/collagen core/shell fibrous scaffolds were hydrophilic having a water contact angle of 17.9 ± 4.6° compared to collagen nanofibers which had a contact angle value of 30 ± 3.2°. The PGS/collagen core/shell fibers had mechanical properties comparable to that of native heart muscle with a young's modulus of 4.24 ± 0.7 MPa, while that of collagen nanofibers was comparatively higher around 30.11 ± 1.68 MPa. FTIR spectrum was performed to confirm the functional groups present in the electrospun scaffolds. Amide Ⅰ and amide Ⅱ of collagen were detected at 1638.95 cm -1 and 1551.64 cm -1 in the electrospun collagen fibers and at 1646.22 cm -1 and 1540.73 cm -1 for PGS/collagen core/shell fibers respectively. Cell culture studies performed using MSCs and cardiac cells co-culture environment, indicated that the cellproliferation significantly increased on PGS/collagen core/shell scaffolds compared to collagen fibers and the cardiac marker proteins actinin and troponin were expressed more on PGS/collagen core/shell scaffolds compared to collagen fibers alone. Dual immunofluorescent staining was performed to further confirm the cardiogenic differentiation of MSCs by employing MSC specific marker protein, CD 105 and cardiac specific marker protein, actinin. SEM observations of cardiac cells showed normal morphology on PGS/collagen fibers and providing adequate tensile strength for the regeneration of myocardial infarction. CONCLUSION: Combination of PGS/collagen fibers and cardiac cells/MSCs co-culture system providing natural microenvironments to improve cell survival and differentiation, could bring cardiac tissue engineering to clinical application.
基金supported by the Natural Science Foundation of Tianjin, China (09JCZDJC18600)the National Natural Science Foundation of China (50573055 & 30828008)
文摘Because of the inherent appearance similar to the natural extracellular matrix,ultrafine fibrous membranes prepared via electrospinning exhibit widespread applications,especially in the biomedical area.Extensional modifications of coaxial and emulsion electrospinning have drawn much attention in preparation of core/shell fibers for applications as tissue engineering scaffolds and controlled delivery systems for bioactive substances.Due to incorporation of multi-components in the electrospun core/ shell fibers,the process of coaxial and emulsion electrospinning became more susceptible.The theories have not been fully understood.A series of investigations were carried out evaluating the systematic and processing parameters.This paper reviews advantages and potentials of electrospun core/shell fibers as well as factors influencing their formation on the basis of our research and new progress.
基金financially supported by the MOS of China (No. 2017YFB0703300)the National Natural Science Foundation ofChina (No. 51673117)the Science and Technology Innovation Commission of Shenzhen (Nos. JSGG20160226201833790, JCYJ20150625102750478)
文摘Polystyrene(PS) fibers with core-shell structures were fabricated by coaxial electrostatic spinning,[10_TD$IF]in which there are liquid epoxy or curing agent as the core and PS as the shell. Scanning electron microscopy(SEM), Fourier transform infrared(FTIR) spectra and optical microscope were utilized for charactering the morphology and composition of the fibers. Composite coatings embedded with the healant-loaded coreshell fibers have been prepared and the self-healing of the scratch on the coatings has been revealed.
文摘采用同轴静电纺丝技术制备聚乳酸(PLA)-聚己内酯(PCL)核-壳结构复合纤维.利用扫描电子显微镜(SEM)观察纺丝电压、收集距离和核层-壳层溶液推进速度对PLA-PCL核-壳结构复合纤维形貌的影响.通过透射扫描电子显微镜(TEM)分析核层-壳层溶液推进速度对PLA-PCL核-壳结构形成的影响.研究结果表明:当核-壳溶液推进速度为0.1-0.2和0.1-0.3 m L/h时形成了清晰的核-壳结构;随着壳层溶液推进速度加快,PLA-PCL复合纤维核层含量降低,增加纺丝电压能够有效地降低复合纤维平均直径,而增大收集距离使复合纤维平均直径先降低后增加.
