Showing 3 results for Nanofibers
Volume 4, Issue 2 (10-2020)
Abstract
The porosity of electrospun nanofibers web is a significant parameter affecting various areas of nanofibers applications. Thus, at first, the effect of most effective parameters, the concentration of polymer solution and flow rate, on the diameter of polyvinyl alcohol nanofibers, as a dissolving component, were investigated. Afterward, the hybrid web of polyamide 6/polyvinyl alcohol (PA/P) was prepared via a two-sided dual-nozzles electrospinning method. The morphology, diameter, pore size of nanofibers web and the effect of dissolving constituent were studied based on images of the scanning electron microscope. To measuring the porosity of nanofibrous webs, three practical and straightforward methods that have been proposed in the literature were utilized. It was observed that when one component was dissolved, the diameter of the resultant web was decreased, and the porosity has been reduced to about 70% based on the best selected method of porosity. Additionally, the average pore size of electrospun PA6 webs has been decreased about 30-58% relative to the original hybrid webs.
, Alireza Naderi Sohi, ,
Volume 7, Issue 2 (9-2016)
Abstract
According to the novel achievements, nanotopography and steric geometry of the microenvironment around the cells have a drastic role on their fates. Hence, fabrication of biocompatible nanostructures as the scaffolds for the cell culture and in the next step, accurate determination of their physical and geometrical characteristics is widely considered. Despite of broad utilization of Atomic Force Microscopy to investigate topological traits of sophisticated nanopatterns; its capability to characterize electrospun nanofibers has not been studied inquiringly. In the present research, chitosan nanofibers which were successfully electrospun at the optimized conditions were then evaluated using Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM) respectively. The results suggested that recruitment of both of these techniques have their own advantages and disadvantages. As the first noticeable issue, while the sample preparation and scanning procedure in SEM imaging may disrupt native structure of fibers, probing the sample by AFM doesn't need any pre-imaging treatment. The main application of SEM in analysis of nanofibrillar structures is the rapid survey of nanofibers shape, orientation, diameter and consistency. In the other side, three dimensional imaging by AFM makes it possible to determine whole surface roughness, roughness along fibers and woven tissue thickness. Furthermore, regarding some technical advices, AFM can be used to estimate nanofibers average diameter as well as SEM.
F. Zamani , A.a. Merati , M. Latifi , H. Ghanbari Alanagh , F. Nadipour ,
Volume 9, Issue 4 (12-2018)
Abstract
Aims: Tissue engineering and replacement of damaged tissue in medical science is very important and more effective than person-to-person transplantation. Therefore, the production of scaffolds from natural and synthetic polymers with desirable properties to reproduce damaged tissues is increasing. The aim of the present study was to investigate the effect of plasma treatment on contact angle or hydrophilicity of poly-lactic glycolic acid nanofibrous scaffolds and cell culture efficiency.
Materials and Methods: In the present experimental research, two types of solvents such as pure chloroform and the choloroform80% and dimethyl formaldehyde20% were used for electrospinning solution. The level of electrospun scaffolds was corrected by plasma technology; then, the African green monkey kidney (VERO) cells were cultured on them. The raw or non-treated electrospun scaffold was compared with that of plasma treated in hydrophilicity and cell culture viewpoints. To compare the hydrophilicity of scaffolds, the contact angle of them was measured.
Findings: The samples treated with plasma show lower contact angle and consequently higher hydrophilicity. C=O and C-O groups increased in the plasma-treated samples in comparison with those of raw samples. Plasma scaffold level correction improved the adhesion, growth, and proliferation of cells compared to non-treated scaffolds.
Conclusion: The contact angle of the plasma-treated samples is significantly reduced. Plasma treatment can increase the hydrophilicity of poly-lactic glycolic acid nanofibrous scaffolds, and cell adhesion and growth on plasma-treated scaffolds is better than cell growth and proliferation on non-treated scaffolds.
