Sharif Digital Repository

In the present study, the feasibility of electrospun polyethersolfone (PES) nanofibrous membrane as the solid substrate for microfluidic based immunoassays to enhance the density of immobilized antibody on the surface of membrane was assessed. Conversely, the efficacy of antibody immobilization was compared by two different strategies as 1-Ethyl-3-(3-dimethylaminopropyl)-carbodiimide (EDC)/N-Hydroxysuccinimide (NHS) coupling chemistry and hydrophobic interaction. Compared to conventional immunoassays carried out in plates or gels, microfluidic based immunoassays grant a lot of advantages such as a consumption of little samples and reagents, shorter analysis time, and higher efficiency.... 

The high aspect ratio and unique thermal and electrical characteristics of carbon nanofiber (CNF) made it an ideal physical barrier against the penetration of corrosive ions. However, the poor compatibility of the CNF with the polymer matrix and the lack of active corrosion inhibitors are the key limitations of this nanomaterial, resulting in short-term anti-corrosion resistance. An intelligent self-healing epoxy (EP) coating, including CNF modified with a polydopamine (PDA)-La3+ complex, was successfully fabricated to overcome these issues. Electrochemical impedance spectroscopy (EIS) evaluation implied that mild steel (MS) submerged in a 3.5 wt % NaCl solution containing the CNF-PDA-La... 

Unique physiochemical and biological properties of nanofibers along with the choice of a wide variety of materials for both fabrication and tunable release patterns make nanofibers an ideal option for drug delivery. Loading antibacterial agents into nanofibers has attracted great deal of attention. Whilst there are several studies focusing on applying new generations of antibacterial materials, antibiotics are still the gold standard in clinical applications. Therefore, we aimed at introducing antibiotic-loaded nanofiber substrates with potential for topical skin delivery applications, reduced consumption of antibiotics and increased storage time. We applied Amoxicillin (AMX) as a model drug... 

Electrospinning of composite polymer solutions provides fantastic potential to prepare novel nanofibers for use in a variety of applications. The addition of graphene (G) and graphene oxide (GO) nanosheets to bioactive polymers was found to enhance their conductivity and biocompatibility. Composite conductive nanofibers of polyaniline (PANI) and polyacrylonitrile (PAN) with G and GO nanosheets were prepared by an electrospinning process. The fabricated membranes were investigated by physical and chemical examinations including scanning electron microscopy (SEM), Raman spectroscopy, x-ray diffraction (XRD) and tensile assay. The muscle satellite cells enriched by a pre-plating technique were... 

The effects of different nano-SiO2 contents on the rheological properties of poly(vinylidene fluoride) (PVDF) solution and mechanical, thermal, structural, and piezoelectric properties of composite nanofibers were investigated. Results showed an increase in fiber diameter (∼125 to 350 nm) and ∼450% increase in tensile strength as the content of nano-SiO2 particles increased. The degree of crystallinity decreased by 19% as the nano-SiO2 content increased by 2% (w/w). Further investigation demonstrated that silica could significantly improve the piezoelectric properties of PVDF nanofibers as the output voltage showed an increase in the presence of silica attributed to change in the crystalline... 

In this research, cellulose acetate butyrate (CAB) electrospun nanofiber membrane (ENM) was prepared by electrospinning method in order to separate the contaminants of an industrial wastewater. The influence of various electrospinning parameters on morphology and average fiber diameter of the membranes were investigated by scanning electron microscopy and image analysis. The permeability of the membranes was evaluated by measuring pure water flux. In order to investigate the performance of the prepared membranes for tomato wastewater treatment, the rejection of the pollution indices and flux were determined. The results demonstrated the potential of using CAB nanofiber membrane for... 

The application of higher order continuum theories, with size effect considerations, have recently been spread in the micro and nano-scale studies. One famous version of these theories is the couple stress theory. This paper utilizes this theory to study the anti-plane problem of an elliptic nano-fiber, embedded in an infinite medium, both made of centrosymmetric isotropic material. In this framework, a characteristic length appears in the formulation, by which examination of the size effect is possible. This work presents an analytical solution for the proposed problem. Copyright © 2008 by ASME  

Prediction of the anti-plane moduli of solids consisting of a given distribution of unidirectionally aligned elliptic multi-coated fibers with interfacial damage is the focus of this paper. The fibers and their coating layers may be in the order of nano or micro scales. All the constituent phases of the composite are supposed to be described in terms of couple stress elasticity. Accordingly, the bounds for the overall shear moduli of the aforementioned composites are provided by employing the principles of minimum potential and complementary energies. Certain subtleties associated with the elliptic multi-coated fibers for three cases of pure sliding (completely damaged), imperfect (partially...