Hydrogels for biomedical applications.

A comprehensive review summarizing the effect of electrospinning parameters and potential applications of nanofibers in biomedical and biotechnology

https://biblio.ugent.be/publication/792032/file/8599453.pdf

Nonthermal Plasma Technology as a Versatile Strategy for Polymeric Biomaterials Surface Modification: A Review

This article attempts to give an overview of the literature on the treatment of textiles with non-thermal plasmas. Because of the enormous amount of potential uses of non-thermal plasmas for the modification of textile products, categorizing the applications is difficult, and therefore a review is given on plasma treatment effects or results rather than on the textile applications that benefit from the treatment.

Non-thermal plasma treatment of textiles

Nanofibres can be fabricated by various methods and perhaps electrospinning is the most facile route. In past years, electrospinning has been used as a synthesis technique and the fibres have been prepared from a variety of starting materials and show various properties. Recently, incorporating functional nanoparticles (NPs) with electrospun fibres has emerged as one of most exciting research topics in the field of electrospinning. When NPs are incorporated, on the one hand the NPs endow the electrospun fibres/mats novel or better performance, on the other hand the electrospun fibres/mats could preserve the NPs from corrosion and/or oxidation, especially for NPs with anisotropic structures. More importantly, electrospinning shows potential applications in self-assembly of nanoscale building blocks for generating new functions, and has some obvious advantages that are not available by other self-assembly methods, i.e., the obtained free-standing hybrid mats are usually flexible and with large area, which is favourable for their commercial applications. In this critical review, we will focus on the fabrication and applications of NPs-electrospun fibre composites and give an overview on this emerging field combining nanoparticles and electrospinning. Firstly, two main strategies for producing NPs-electrospun fibres will be discussed, i.e., one is preparing the NPs-electrospun fibres after electrospinning process that is usually combined with other post-processing methods, and the other is fabricating the composite nanofibres during the electrospinning process. In particular, the NPs in the latter method will be classified and introduced to show the assembling effect of electrospinning on NPs with different anisotropic structures. The subsequent section describes the applications of these NPs-electrospun fibre mats and nanocomposites, and finally a conclusion and perspectives of the future research in this emerging field is given.

Nanoparticles meet electrospinning: recent advances and future prospects

Durable antibacterial Ag/polyacrylonitrile (Ag/PAN) hybrid nanofibers prepared by atmospheric plasma treatment and electrospinning

A novel and facile one-step approach to in situ synthesize silver nanoparticle-filled nylon 6 nanofibers by electrospinning is reported. The method does not need post-treatments and can be carried out at ambient conditions without using additional chemicals. It employs the electrospinning solvent as a reducing agent for in situ conversion of AgNO3 into silver nanoparticles during the solution preparation. The resultant silver nanoparticle-filled nylon 6 hybrid nanofibers show an excellent fibrous structure (fiber diameter at 50–150 nm), with narrow size 2–4 nm silver nanoparticles uniformly dispersed throughout the nylon 6 matrix. DSC analysis shows that the in situ incorporation of silver nanoparticles increased the Tg and crystallinity of the resultant nanofibers. These silver nanoparticle-filled nylon 6 nanofibers exhibit a steady and long-lasting silver ion release behavior, and robust antibacterial activity against both Gram-positive B. cereus and Gram-negative E. coli microorganisms.

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One-step synthesis of silver nanoparticle-filled nylon 6 nanofibers and their antibacterial properties

Polypropylene and nylon 66 fabrics are subjected to atmospheric pressure He and He-O2 plasmas for selected exposure time intervals. Scanning electron microscopy anal ysis of the fabrics shows no apparent changes in the plasma-treated nylon fiber surfaces, but significant surface morphological changes for the polypropylene. Surface analyses of the nylon filaments reveal small differences in the surface carbon and oxygen contents between the treated and control groups. The surface oxygen and nitrogen content of the polypropylene fabric increases significantly after treatment in both He and He-O2 plasmas. There is a slight decrease in nylon fabric tensile strength after treatment in He plasma for 3 minutes, while. there is no significant change in tensile strength of the nylon fabric treated with He-O2 after exposure times of up to 8 minutes.

Modifying Nylon and Polypropylene Fabrics with Atmospheric Pressure Plasmas

Both air/He and air/O 2/He atmospheric plasma treatments are applied to desize PVA on cotton, then PDR (percent desizing ratio) and tensile strengths of cotton fabrics and single yams are measured. XPS and SEM are used to analyze the effects of atmospheric pressure plasma treatments on PVA. These treatments can both remove some PVA sizing and significantly improve PDR by washing, especially by cold water washing. The tensile strengths of cotton fabrics treated with atmospheric pressure plasma are the same as for the unsized fabric. XPS analysis of the plasma treated PVA films reveals surface chemical changes such as chain scission and formation of polar groups, which promote the solubility of PVA in cold water. Air/O2/He plasma is more effective than air/He plasma on PVA desizing.

Effect of Atmospheric Plasma Treatment on Desizing of PVA on Cotton

Cotton fabrics were treated by radio-frequency plasma with tetrafluoromethane (CF4) and hexafluoropropene (C3F6) gases under different exposure times, pressures, and power levels. The hydrophobicity and water repellency were analyzed with measurements of the cosine of the contact angle (cos θ) and wet-out time. The hydrophobicity was enhanced with treatments of both gases. X-ray photoelectron spectroscopy (XPS) revealed increases in the surface fluorine content of 1–2% for CF4 plasma and of 2.3–7.8% for C3F6 plasma. The relative chemical composition of the C1s spectra after CF4 and C3F6 plasma treatments showed increases in the relative amounts of COC and fluorocarbon groups (CF, CF2, and CF3), whereas peak areas for COH and COOH decreased. The hydrophobicity was enhanced by the increase in the fluorine content and fluorocarbon groups. C3F6 plasma treatment resulted in higher hydrophobicity than CF4 plasma treatment according to not only cos θ and wet-out measurements but also XPS analysis. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 2038–2047, 2003

Marian McCord

Papers

Durable antibacterial Ag/polyacrylonitrile (Ag/PAN) hybrid nanofibers prepared by atmospheric plasma treatment and electrospinning

One-step synthesis of silver nanoparticle-filled nylon 6 nanofibers and their antibacterial properties

Modifying Nylon and Polypropylene Fabrics with Atmospheric Pressure Plasmas

Effect of Atmospheric Plasma Treatment on Desizing of PVA on Cotton

Surface analysis of cotton fabrics fluorinated in radio-frequency plasma