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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 objective of this study was to report the drug delivery system that can integrate the functional building blocks for optical pH-sensing, cancer cell imaging and controlled drug release into a single nanoparticle. The CD/SAHA-QDs-CS/FA nanoparticles were prepared by in-situ immobilization of ZnSe/ZnS quantum dots (QDs) in β-cyclodextrin (CD) and chitosan (CS) polymer loaded with suberoylanilide hydroxamic acid (SAHA). Synthetic CD/SAHA-QDs-CS/FA nanoparticles were approximately 100 nm in size and with blue fluorescence. The drug encapsulation efficiency of nanoparticles was 22.36 % and the encapsulated drug was released via a controlled release mechanism after a 9 h plateau was reached. The efficiency of the drug release in tumor microenvironments (pH 5.3 buffer solutions) was higher than that in physiological pH 7.4. In vitro cytotoxicity assay results showed that the blank nanoparticles had no cytotoxicity and therefore can be used as the fluorescence tracer, and the SAHA-encapsulated nanoparticles expressed an anticancer effect. Confocal microscopy and in vivo imaging studies showed that the developed nanoparticles had cytotoxicity in resistant cancer cells and preferentially accumulated in tumors. CD/SAHA-QDs-CS/FA nanoparticles with excellent long-term optical properties have great prospects for the development of targeting tracers and anti-tumor biomedical research. [ABSTRACT FROM AUTHOR]