Zahra Rezvani; Mazaher Gholipourmalekabadi; Saeid Kargozar; Peiman Brouki Milan; Masoud Mozafari
Abstract
In this study, organic montmorillonite (OMMT) is a modified form of montmorillonite (MMT) in which chitosan (CS) intercalated MMT by ion exchange of sodium ions from Na/MMT with –NH3 + of CS. The structural analysis confirmed intercalation of CS into MMT layers, indicating that CS molecular chains ...
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In this study, organic montmorillonite (OMMT) is a modified form of montmorillonite (MMT) in which chitosan (CS) intercalated MMT by ion exchange of sodium ions from Na/MMT with –NH3 + of CS. The structural analysis confirmed intercalation of CS into MMT layers, indicating that CS molecular chains incorporated into the MMT layers. The interlayer distance of the MMT layered was 1.128nm and in the OMMT layers enlarged to 2.365 nm. Antibacterial activity analysis showed that unmodified MMT could not inhibit the growth of bacteria. Nevertheless, after addition of the CS molecules, an increase in the interlayer distance of MMT was observed. No difference was observed between the viability of the human dental pulp stem cells (hDPSCs) contacted to different concentrations (ranging from 0.5 to 2mg/ml) of MMT and OMMT in all time intervals, when compared with the control samples. Furthermore, neither MMT nor OMMT showed apoptosis and cytotoxicity effect on the cells. The strong antibacterial activity of the synthesized OMMT nanocomposite was also confirmed against E. coli, S. aureus, K. pneumonia and P. aeruginosa, suggesting its high potential for the prevention of post-surgical infections.
Farnaz Ghorbani; Hanieh Nojehdehyan; Ali Zamanian; Mazaher Gholipourmalekabadi; Masoud Mozafari
Abstract
There have been several attempts to synthesis biodegradable polymeric constructs with adequate porous structures for soft connective tissues. In this study, randomly-oriented PLGA-gelatin nanofibrous scaffolds were synthesized by electrospinning method. We offered an appropriate solvent (2, 2, 2-trifluoroethanol) ...
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There have been several attempts to synthesis biodegradable polymeric constructs with adequate porous structures for soft connective tissues. In this study, randomly-oriented PLGA-gelatin nanofibrous scaffolds were synthesized by electrospinning method. We offered an appropriate solvent (2, 2, 2-trifluoroethanol) to dissolve both polymers for achieving a homogenous solution without inducing any toxic effects. The results confirmed the formation of high porous and bead free scaffolds, in which an increase in the injection rate slightly decreased the mechanical, swelling ratio and biodegradation behaviors. The modulus and tensile strength for the scaffolds with the injection rate of 0.2 ml/hr were 0.72 ±0.02 and 2.70 ±0.33, respectively. In addition, the evaluation of cell proliferation demonstrated that L929 fibroblast cells spread well on the scaffolds, indicating that they are able to support cell attachment. A possible chemical bond formation has been also suggested for the blending mixture of PLGA and gelatin molecules.
Mazaher Gholipourmalekabadi; Masoud Mozafari; Mojgan Bandehpour; Marzieh Sameni; Hossein Ghanbarian
Abstract
In this study, the effects of ethanol treatment on the mechanical and biological characteristics of the nanofibrous silk fibroin (NSF) scaffolds were evaluated. The results obtained from the mechanical tests confirmed that ethanol treatment significantly enhanced the physical properties of the scaffolds ...
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In this study, the effects of ethanol treatment on the mechanical and biological characteristics of the nanofibrous silk fibroin (NSF) scaffolds were evaluated. The results obtained from the mechanical tests confirmed that ethanol treatment significantly enhanced the physical properties of the scaffolds through the formation of a ß-sheet structure. It was shown that the ethanol treatment increased the mechanical property and cell viability, while decreased the porosity of the randomly arranged uniform nanofibers. The ultimate tensile strength for the NSF and ethanol-treated NSF (ET-NSF) scaffolds were 0.76 and 1.33 MPa, respectively. In addition, the ethanol treatment positively affected the proliferation rate of rat bone-marrow stromal cells (rBMSCs) without any detectable cytotoxicity. All the results obtained from this study strongly indicated the efficacy of ethanol treatment in enhancement of mechanical and biological characteristics of silk fibroin nanofibrous scaffolds.
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