Electrospun nylon-6 spider-net like nanofiber mat containing TiO(2) nanoparticles: a multifunctional nanocomposite textile material.

In this study, electrospun nylon-6 spider-net like nanofiber mats containing TiO(2) nanoparticles (TiO(2) NPs) were successfully prepared. The nanofiber mats containing TiO(2) NPs were characterized by SEM, FE-SEM, TEM, XRD, TGA and EDX analyses. The results revealed that fibers in two distinct sizes (nano and subnano scale) were obtained with the addition of a small amount of TiO(2) NPs. In low TiO(2) content nanocomposite mats, these nanofiber weaves were found uniformly loaded with TiO(2) NPs on their wall. The presence of a small amount of TiO(2) NPs in nylon-6 solution was found to improve the hydrophilicity (antifouling effect), mechanical strength, antimicrobial and UV protecting ability of electrospun mats. The resultant nylon-6/TiO(2) antimicrobial spider-net like composite mat with antifouling effect may be a potential candidate for future water filter applications, and its improved mechanical strength and UV blocking ability will also make it a potential candidate for protective clothing.

In vitro bioactivity of sol-gel-derived hydroxyapatite particulate nanofiber modified titanium.

A chemically-etched titanium surface was modified by electrospinning a sol-gel-derived hydroxyapatite (HAp) that was subjected to calcination within the temperature range of 200-1400 degrees C in the normative atmospheric condition. After heat treatment, crystal structures of the filmed titanium oxide and HAp on the titanium's surface were identified using wide-angle X-ray diffraction. A highly porous layer of HAp was found to have formed on the oxidized titanium surfaces. The surfaces of three different samples; (1) electrospun HAp, (2) HAp calcined at 600 degrees C, and (3) HAp calcined at 800 degrees C, were investigated for their ability to foster promotion, proliferation, and differentiation of human osteoblasts (HOB) (in the 9th passage) in vitro up to 6 days. Among the three samples, cells cultured on the HAp calcined at 800 degrees C titanium surfaces displayed the best results with regard to adhesion, growth, and proliferation of HOB. This novel method for fabrication of titanium substrates would provide a promising improvement for titanium-based medical devices over the current standards, which lack such substrates. These titanium substrates explicitly provide enhanced HOB proliferation in terms of both desired surface properties and their produced bulk quantity.

Biomimetic hydroxyapatite particulate nanofiber modified silicon: in vitro bioactivity.

A novel particulate nanofibrous hydroxyapatite (HA), which mimics the bone matrix, is presented as a surface functional material to modify silicon wafers by the electrospinning method. The HA precursors were treated with viscous polymer solution, and then electrospun under controlled conditions. After successive calcinations, the powder X-ray diffraction patterns of the samples revealed reflection toward the (300) HA plane that is linear with temperature. This prominent reflection suggests the crystallographic purity of the HA. Biocompatibility, cell proliferation, and microstructure were examined using AFM and FE-SEM. Morphology showed cell spreading and penetration instead of cell aggregation. The surface roughness as well as adhesion force was calculated using contact mode AFM. The results show that the composite matrix holds promise for use as a bone implant material.

Synchronized polymerization and fabrication of poly(acrylic acid) and nylon hybrid mats in electrospinning.

Acrylic acid monomer in a viscous supporting nylon solution was polymerized and fabricated simultaneously via an electrospinning process. This novel polymerization method defines the fiber morphology as a network of interconnected mats. This network consists of smaller poly(acrylic acid) (PAA) fibers, approximately 19 nm in diameter, and larger nylon 6 fibers, approximately 75 nm in diameter. These two different fibers are separated by extraction of PAA from the fibrous mat in water and differentiation of field-emission scanning electron microscopy (FESEM) images of the same mat using before and after extraction of PAA. The structure of the extracted PAA was confirmed by 1H NMR and Fourier transform infrared (FT-IR) analysis. The observed modification to conventional electrospun mats is due to the presence of an extra phase-separated PAA produced by the electrospinning polymerization process. Finally, fiber morphologies and hybrid property were characterized via FT-IR, FESEM, thermogravimetric analysis, and X-ray diffraction. Similarly extracted samples and synthesis PAA were characterized in FT-IR and 1H NMR spectroscopy.