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Introduction: In this study, the silk fibroin blended constructs were produced, scaffold performances of different kinds of scaffold were analyzed, and the better type for tissue engineering was optimized. Methods: The silk fibroin/collagen (SF/C) and silk fibroin/chitosan (SF/CS) were made using a freeze-drying technique, porosity, water absorption expansion rate, mechanical properties and pore size of different scaffold was detected. Bone marrow mesenchymal stem cells (BMSCs) of 4-week-old male Wistar rats were separated by density gradient centrifugation, third generation BMSCs were seeded onto scaffolds, cultured 14 days, proliferation and metabolize of cells were detected in different time using the thiazolyl blue tetrazolium bromide (MTT) assay method, and cell morphology and distribution were observed by histological analysis and scanning electron microscopy (SEM). Results: Porosity, water absorption expansion rate and Young's modulus of SF/C were significantly higher than SF/CS ( p < 0.05); pore size of SF/C and SF/CS was 103 ± 12 and 76 ± 11 μm and had no significant differences between two types ( p > 0.05); MTT results showed that the metabolism of cells in the SF/C was better than SF/CS; after cultivation for 14 days, in the inner zone of scaffolds, cells staining were little or absent from SF/CS, lots of cells staining were existing in SF/C; pore size was consistent, holes communicated with each other better, stem cells grew well inside the scaffolds, extended fully and secreted much extracellular matrix under SEM in SF/C scaffold; internal structure of SF/CS was disorder, holes size were not consistent, and did not communicated with each other and cells were partly dead. Conclusion: Compared with SF/CS, SF/C scaffold showed better porosity, water absorption expansion rate, elasticity modulus and pore size, cells grow well inside the scaffolds, and was more suitable for tissue engineering. [ABSTRACT FROM AUTHOR]

The property of collagen–chitosan porous scaffold varies according to cross-linking density and scaffold composition. This study was designed to compare the properties of collagen–chitosan porous scaffolds cross-linked with γ-irradiation and carbodiimide (CAR) for the first time. Eleven sets of collagen–chitosan scaffolds containing different concentrations of chitosan at a 5% increasing gradient were fabricated. Fourier transform infrared spectroscopy was performed to confirm the success of cross-linking in the scaffolds. The scaffold morphology was evaluated under scanning electron microscope (SEM). SEM revealed that chitosan was an indispensable material for the fabrication of γ-ray irradiation scaffold. The microstructure of γ-ray irradiation scaffold was less stable than those of alternative scaffolds. Based upon swelling ratio, porosity factor, and collagenase degradation, γ-ray irradiation scaffold was less stable than CAR and 25% proportion of chitosan scaffolds. Mechanical property determines the orientation in γ-irradiation and CAR scaffold.In vitrodegradation test indicated that γ-irradiation and CAR cross-linking can elevate the scaffold biocompatibility. Compared with γ-ray irradiation, CAR cross-linked scaffold containing 25% chitosan can more significantly enhance the bio-stability and biocompatibility of collagen–chitosan scaffolds. CAR cross-linked scaffold may be the best choice for future tissue engineering. [ABSTRACT FROM PUBLISHER]