- Email: [email protected]
silk fibroin nanofibrous scaffolds for nerve tissue regeneration
Abstracts / Journal of Controlled Release 259 (2017) e5–e195
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[2] K.R. Deng, Z.Y. Hou, X.R. Deng, P.P. Yang, C.X. Li, J. Lin, Enhanced antitumor efficacy by 808 nm laser-induced synergistic photothermal and photodynamic therapy based on a indocyanine-green-attached W18O49 nanostructure, Adv. Funct. Mater. 25 (2015) 7280-7290.
Natural Science Foundation of China (31470938, 11421202, 61227902, and 11120101001).
doi:10.1016/j.jconrel.2017.03.338
[1] N. Li, X. Zhang, Q. Song, R. Su, Q. Zhang, T. Kong, L. Liu, G. Jin, M. Tang, G. Cheng, The promotion of neurite sprouting and outgrowth of mouse hippocampal cells in culture by graphene substrates, Biomaterials 32 (2011) 9374-9382. [2] S. Shah, P. Yin, T. Uehara, S. Chueng, L. Yang, K. Lee, Guiding Stem Cell Differentiation into Oligodendrocytes Using Graphene-Nanofiber Hybrid Scaffolds, Adv. Mater. 26 (2014) 3673-3680.
Fabrication and characterization of aligned graphene/silk fibroin nanofibrous scaffolds for nerve tissue regeneration ⁎
References
doi:10.1016/j.jconrel.2017.03.339
⁎
Yi Yang, Xili Ding, Tongqiang Zou, Yuan Yao, Haifeng Liu , Yubo Fan Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, International Research Center for Implantable and Interventional Medical Devices, School of Biological Science and Medical Engineering, Beihang University, Beijing 100191, China ⁎Corresponding authors. E-mail addresses: [email protected] (H. Liu), [email protected] (Y. Fan) Neural system is an ideal breakthrough model in the biomedical applications of graphene since graphene has higher electrical conductivity [1]. In addition, graphene has been demonstrated to promote neural cell proliferation and the differentiation of neual stem cells [2]. Herein, aligned graphene/silk fibroin (G/SF) nanobrous scaffolds with different contents of graphene (0, 0.1%, 0.2%, 0.3%, and 0.4%) were fabricated and explored for the potential application for nerve regeneration. The morphology and dispersion of graphene nanosheets in SF matrix were characterized by SEM, TEM and Raman spectroscopy. It was found that graphene could be well dispered within the SF matrix. The diameters of the G/SF nanofibrous scaffolds increased initially with the graphene content and then leveled-off. Moreover, the thermal and mechanical properties of the scaffolds were examined. The results showed that the tensile strength and modulus of the nanofibrous scaffolds increased with the addition of graphene within a certain concentration of graphene (Fig. 1). In addition, the electrospun nanofibrous G/SF scaffolds also exhibited improved thermal stability with the addition of graphene. Resistance meter will be used to measure the electrical conductivity of the G/SF scaffolds. Further studies will be conducted to test the cellular compatibility of the nanofibrous scaffolds for the application in nerve tissue regeneration in the future.
Supramolecular aggregates for high-efficient gene delivery Yi Zhang, Dong Ma⁎, Wei Xue⁎ Key Laboratory of Biomaterials of Guangdong Higher Education Institutes, Department of Biomedical Engineering, Jinan University, Guangzhou 510632, China ⁎Corresponding authors. E-mail addresses: [email protected] (D. Ma), [email protected] (W. Xue) Gene therapy as a promising therapeutic approach for cancer treatment has drawn great attention for the past decades [1]. Nowadays, the biggest challenge for synthetic gene carriers is how to enhance the gene delivery efficacy while maintaining their good biocompatibility. To realize that, most scientists focus on designing polymers with increased amine number and charge density [2], which are of pivotal importance for their gene transfection. But the synthesis process and structure control are difficult, and high molecular weight and high charge density also bring high cytotoxicity [3]. Inspired by the excellent gene delivery effect of virus and liposomes, we used physical interactions to construct assembly/ aggregation complexes for gene delivery. Herein, we reported on aggregates from the host-guest interaction between low molecular PEI-conjugating 2-β-CD and diferrocene-ended polyethylene glycol as new gene carriers (Fig. 1). The aggregates displayed excellent gene delivery ability under the optimized experimental conditions, even better than PEI-25k. In vitro assays confirmed that the aggregates could deliver MMP-9 shRNA plasmid effectively into MCF-7 cells, inducing significant apoptosis of MCF-7 cells as compared to PEI-25k. Remarkably, the in vivo experiments in MCF-7 tumor-bearing mice showed inhibition of MCF-7 tumor growth and low systemic toxicity. Considering the difficult in synthesizing the topological polymers with complex structures, Therefore, the results demonstrated the potential applications of the aggregates formed from supramolecular interactions in gene therapy.
Fig. 1. The stress-strain curves of prepared G/SF scaffolds (A), and the representative SEM micrographs of aligned G/SF fibers (B).
Keywords: graphene, silk fibroin, nanofibrous scaffolds, nerve regeneration Acknowledgements The authors are grateful for the National Key Technology R&D Program (2012BAI18B06, 2014BAI11B02, 2014BAI11B03) and National
Fig. 1. Illustration of the preparation and structure of PEI-CD/PEG-Fc assembly and its application for the delivering of the therapeutic MMP-9 gene to tumor cells.
e171
[2] K.R. Deng, Z.Y. Hou, X.R. Deng, P.P. Yang, C.X. Li, J. Lin, Enhanced antitumor efficacy by 808 nm laser-induced synergistic photothermal and photodynamic therapy based on a indocyanine-green-attached W18O49 nanostructure, Adv. Funct. Mater. 25 (2015) 7280-7290.
Natural Science Foundation of China (31470938, 11421202, 61227902, and 11120101001).
doi:10.1016/j.jconrel.2017.03.338
[1] N. Li, X. Zhang, Q. Song, R. Su, Q. Zhang, T. Kong, L. Liu, G. Jin, M. Tang, G. Cheng, The promotion of neurite sprouting and outgrowth of mouse hippocampal cells in culture by graphene substrates, Biomaterials 32 (2011) 9374-9382. [2] S. Shah, P. Yin, T. Uehara, S. Chueng, L. Yang, K. Lee, Guiding Stem Cell Differentiation into Oligodendrocytes Using Graphene-Nanofiber Hybrid Scaffolds, Adv. Mater. 26 (2014) 3673-3680.
Fabrication and characterization of aligned graphene/silk fibroin nanofibrous scaffolds for nerve tissue regeneration ⁎
References
doi:10.1016/j.jconrel.2017.03.339
⁎
Yi Yang, Xili Ding, Tongqiang Zou, Yuan Yao, Haifeng Liu , Yubo Fan Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, International Research Center for Implantable and Interventional Medical Devices, School of Biological Science and Medical Engineering, Beihang University, Beijing 100191, China ⁎Corresponding authors. E-mail addresses: [email protected] (H. Liu), [email protected] (Y. Fan) Neural system is an ideal breakthrough model in the biomedical applications of graphene since graphene has higher electrical conductivity [1]. In addition, graphene has been demonstrated to promote neural cell proliferation and the differentiation of neual stem cells [2]. Herein, aligned graphene/silk fibroin (G/SF) nanobrous scaffolds with different contents of graphene (0, 0.1%, 0.2%, 0.3%, and 0.4%) were fabricated and explored for the potential application for nerve regeneration. The morphology and dispersion of graphene nanosheets in SF matrix were characterized by SEM, TEM and Raman spectroscopy. It was found that graphene could be well dispered within the SF matrix. The diameters of the G/SF nanofibrous scaffolds increased initially with the graphene content and then leveled-off. Moreover, the thermal and mechanical properties of the scaffolds were examined. The results showed that the tensile strength and modulus of the nanofibrous scaffolds increased with the addition of graphene within a certain concentration of graphene (Fig. 1). In addition, the electrospun nanofibrous G/SF scaffolds also exhibited improved thermal stability with the addition of graphene. Resistance meter will be used to measure the electrical conductivity of the G/SF scaffolds. Further studies will be conducted to test the cellular compatibility of the nanofibrous scaffolds for the application in nerve tissue regeneration in the future.
Supramolecular aggregates for high-efficient gene delivery Yi Zhang, Dong Ma⁎, Wei Xue⁎ Key Laboratory of Biomaterials of Guangdong Higher Education Institutes, Department of Biomedical Engineering, Jinan University, Guangzhou 510632, China ⁎Corresponding authors. E-mail addresses: [email protected] (D. Ma), [email protected] (W. Xue) Gene therapy as a promising therapeutic approach for cancer treatment has drawn great attention for the past decades [1]. Nowadays, the biggest challenge for synthetic gene carriers is how to enhance the gene delivery efficacy while maintaining their good biocompatibility. To realize that, most scientists focus on designing polymers with increased amine number and charge density [2], which are of pivotal importance for their gene transfection. But the synthesis process and structure control are difficult, and high molecular weight and high charge density also bring high cytotoxicity [3]. Inspired by the excellent gene delivery effect of virus and liposomes, we used physical interactions to construct assembly/ aggregation complexes for gene delivery. Herein, we reported on aggregates from the host-guest interaction between low molecular PEI-conjugating 2-β-CD and diferrocene-ended polyethylene glycol as new gene carriers (Fig. 1). The aggregates displayed excellent gene delivery ability under the optimized experimental conditions, even better than PEI-25k. In vitro assays confirmed that the aggregates could deliver MMP-9 shRNA plasmid effectively into MCF-7 cells, inducing significant apoptosis of MCF-7 cells as compared to PEI-25k. Remarkably, the in vivo experiments in MCF-7 tumor-bearing mice showed inhibition of MCF-7 tumor growth and low systemic toxicity. Considering the difficult in synthesizing the topological polymers with complex structures, Therefore, the results demonstrated the potential applications of the aggregates formed from supramolecular interactions in gene therapy.
Fig. 1. The stress-strain curves of prepared G/SF scaffolds (A), and the representative SEM micrographs of aligned G/SF fibers (B).
Keywords: graphene, silk fibroin, nanofibrous scaffolds, nerve regeneration Acknowledgements The authors are grateful for the National Key Technology R&D Program (2012BAI18B06, 2014BAI11B02, 2014BAI11B03) and National
Fig. 1. Illustration of the preparation and structure of PEI-CD/PEG-Fc assembly and its application for the delivering of the therapeutic MMP-9 gene to tumor cells.