Membranes electrospun

Yang DJ et al (2007) Fabrication and characterization of hydrophilic electrospun membranes made from the block copolymer of poly(ethylene glycol-co-lactide). J Biomed Mater Res A 82(3) 680-688... 

Jiang HL et al (2004) Preparation and characterization of ibuprofen-loaded poly(lactide-co-glycolide)/poly(ethylene glycol)-g-chitosan electrospun membranes. J Biomater Sci Polym Ed 15(3) 279-296... 

About lO.Omg of thermally crosslinked PAA/PVA electrospun fibrous membrane was immersed in 2.0ml of the selected pH buffer solution with the lipase concentration at 5.0mg/ml. After the mixture was incubated in the water bath at 30°C for 24 hrs, the fibrous membrane was taken out and rinsed with the same pH buffer. The washing pH buffer was added to the residue solution left fi-om the adsorption to make up the total solution volume to be exactly 10.0ml in a volumetric flask. The concentration of lipase in the above solution was then determined by Bio-Rad (Hercules, CA) protein assay (7, //). The amount of lipase physically adsorbed by the electrospun membrane was calculated by deducting the lipase amount in the buffer solution fi om the original total amount. The average fi om measurements of three samples was reported. 

Method /. 10 mg of PAA/PVA electrospun membrane was swollen at 30°C in 2.0 ml of pH4 buffer solution containing both EDC (EDC COOH of PAA = 2 1 in molar ratio) and lipase (5mg/ml). After 24 hrs, the membrane was washed thoroughly with pH4 buffer and deionized water, and dried in vacuum at room temperature. 

Alvarez-Perez, M.A., et al., 2010. Influence of gelatin cues in PCL electrospun membranes on nerve outgrowth. Biomacromolecules 11 (9), 2238—2246. 

R, Ng WJ, Ramakrishna S, and Matsuura T, Next-generation fibrous media for water treatment, MRS Bulletin 2008, 33, 21-26 (c) Kaur S, Rana D, Matsuura T, Sundarrajan S, and Ramakrishna S, Preparation and characterization of surface modified electrospun membranes for higher filtration fiux. Journal of Membrane Science 2012, 390-391, 235-242 (d) Kaur S, Sundarrajan S, Rana D, Matsuura T, and Ramakrishna... 

Figure 8.12 Stress-strain curves for P(LLA-GA) (mol/mol=10/90) electrospun membranes prepared under the 2 kV/cm electric field, at a feed rate of 100 j,l/min and different concentrations of 7.5, 10 and 15 wt%, respectively [147], (Reproduced with permission from 1147]. Copyright Elsevier, 2003.)...

PANI and polyfc-caprolactone] (PCL] showed similar behavior and their electrospun membranes can be used as platforms to mimic either the morphological or the functional features of the cardiac muscle tissue regeneration. Development of PANI/PCL membranes by electrospinning with controlled texture can create an electrically conductive environment and this environment can stimulate the cell differentiation to cardiomyocites and can be used in the myocardium muscle regeneration. 

C.M., Gomez Ribelles, J.L., and Lanceros-Mendez, S. (2011) Xailoring the morphology and crystallinity of poly(L-lactide acid) electrospun membranes. ScL Techncl. Adv. Mater., 12, 015001. 

J.L.G, and Lanceros-Mendez, S. (2010) Influence of processing conditions on polymorphism and nanofiber morphology of electroactive poly(vinylidene fluoride) electrospun membranes. Soft Mater., 8, 274-287. 

Dilamiana, M., Montazerb, M., and Masoumic, J. (2013) Antimicrobial electrospun membranes of chitosan/poly(ethylene oxide) incorporating poly(hexamethylene biguanide) hydrochloride. Carhohydr. Polym., 94, 364-371. 

Fig. 19 (a) Water contact angle measurements as a function of time of (A) electrospun PCL/bioactive glass fibers with diameters of 260 60 nm, (S) electrospun PCL/bioactive glass fibers with diameters of 600 166 nm, and (C) electrospun PCL control scaffold. Reprinted with permission from [164], Copyright (2013) American Chemical Society, (b) Representative stress-strain curves of PCL/S102 electrospun membranes at different wt% compositions. Reprinted with permission from [137], Copyright (2010) Elsevier... 

As an alternative approach to blending, natural and synthetic polymers can be combined in fibrous scaffolds fabricated by core—shell techniques. Chen et al. (2010) prepared nanofibrous scaffolds by core—shell electrospinning based on a commercial thermoplastic PUR and collagen as the fibre core and shell, respectively. The collagen shell was cross-linked by glutaraldehyde vapours. The electrospun mats showed an intermediate mechanical behaviour as compared to the pure component electrospun membranes moreover, the core—shell electrospun membranes were found to support in vitro adhesion and proliferation of pig iliac endothelial cells. 

Through ultrafine fiber and high fiber density, porosity of fibrous stmctures could be decreased and inhibit cellular ingrowth within the substitute fibrous stmcture. The dense fiber network of electrospun membrane presents a barrier for cell entry. It has been used for islets, which are used as an immiinoisolation strategy for disease... 

Krishna L, Clayton LR, Boland ED, Reed RM, Hoying JB, Williams SK. Cellular immunoisolation for islet transplantation hy a novel dual porosity electrospun membrane. Transpl Proc 2011 43 3256-61. 

The scanning decticm microscope (SEM) images of electrospun membrane of the FMMA-PM and cross-linked PAA-PM are shown in Figure 4. It was observed that the membranes have three-dimensional structures with a random fiber orioitation that is uniformly distributed on the substrate. The diameters of the fibers were rqrproximatefy 400 to 1000 run for PMMA-PM and 100 to 400 run for PAA-PM. The porous structure of electrospun membrane provides 1 to2 orders of magnitude Iti er airfoce area to volume ratio than known for continuous thin films. 

Figure 4. SEM images of electrospun membranes PKtMA-PA 0tfi) and...

Figure 5. Fluorescence emission spectra of a PMMA-PM electrospun membrane with varying DNT concentration.

Bhattarai et al. developed a novel biodegradable electrospun membrane as a scaffold for tissue engineering. A nanofibrous matrix of poly(p-dioxanone-co-L-lactide)-block-poly(ethylene glycol) (PPDO/PLLA-b-PEG) copolymer was evaluated for cell proliferation and its morphology of cell-matrix interaction. The electrospun structure composed of fibers with an average diameter of 380 nm, medium pore size 8 mm, porosity greater than 80% and mechanical strength of 1.4 MPa is favorable for cell-matrix interaction [39]. 

In addition, differently from hydrophilic natural fibers such as cotton, Rp of PAN or poly(benzimidazole) (PBI) electrospun membranes is practically... 

McKee MG, Layman JM, Cashion MP, Long TE (2006) Phospholipid nonwoven electrospun membranes. Science 311(5759) 353-355... 

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