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For the past three decades, research interest in electrospinning (ES) has grown exponentially. Twenty years ago, the initial reports on the utilization of this rather simple ultrafine fiber-forming method in combination with a widely established materials chemistry tool known as sol–gel (SG) and without the aid of electrospun organic fibers as templates (or fiber-forming sacrificial polymers) were published in the open literature. In parallel, several groups right around the same time also proposed the use of long-chain organic polymers in SG formulations to facilitate their spinnability into ultrafine fibers. Since then, the number of research articles exploring SG-ES to produce inorganic fibers with submicron diameters has also grown steadily, resulting in several identifiable R&D sub-fields. Relatively recent advances in ES scalability have now made it even more attractive for exploring potential commercial applications. This review is an attempt to provide readers with a comprehensive overview of SG-ES work done in the areas of metal oxide catalysis, photocatalysis, and adsorption. It does not focus on devices having a catalytic function, such as fuel cells and sensors, but on materials whose end goal is to be used as catalysts or sorbents. A number of potentially valuable opportunities and recommendations are also offered. [ABSTRACT FROM AUTHOR]

A focused, brief review on the issue of needleless electrohydrodynamic (EHD) methods for making submicron fibers and particles is presented. Advantages over conventional EHD methods, especially on the issue of production scale, are discussed. An overview of key, entry-point patent, and journal literature are offered to assist the materials processing engineer in the equipment design selection. [ABSTRACT FROM AUTHOR]

Tissue-engineered neocartilage with appropriate biomechanical properties holds promise not only for graft applications but also as a model system for controlled studies of chondrogenesis. Our objective in the present research study is to better understand the impact of fiber diameter on the cellular activity of chondrocytes cultured on nanofibrous matrices. By using the electrospinning process, fibrous scaffolds with fiber diameters ranging from 300 nm to 1 μm were prepared and the physicomechanical properties of the scaffolds were characterized. Bovine articular chondrocytes were then seeded and maintained on the scaffolds for 7 and 14 days in culture. An upregulation in the gene expression of collagen II was noted with decreasing fiber diameters. For cells that were cultured on scaffolds with a mean fiber diameter of 300 nm, a 2-fold higher ratio of collagen II/collagen I was noted when compared to cells cultured on sponge-like scaffolds prepared by freeze drying and lyophilization. Integrin (α5, αv, β1) gene expression was also observed to be influenced by matrix morphology. Our combined results suggest that matrix geometry can regulate and promote the retention of the chondrocyte genotype. Copyright © 2011 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]