Extracellular polymeric substances (EPS) produced by microorganisms are a complex mixture of biopolymers primarily consisting of polysaccharides, as well as proteins, nucleic acids, lipids and humic substances. EPS make up the intercellular space of microbial aggregates and form the structure and architecture of the biofilm matrix. The key functions of EPS comprise the mediation of the initial attachment of cells to different substrata and protection against environmental stress and dehydration. The aim of this review is to present a summary of the current status of the research into the role of EPS in bacterial attachment followed by biofilm formation. The latter has a profound impact on an array of biomedical, biotechnology and industrial fields including pharmaceutical and surgical applications, food engineering, bioremediation and biohydrometallurgy. The diverse structural variations of EPS produced by bacteria of different taxonomic lineages, together with examples of biotechnological applications, are discussed. Finally, a range of novel techniques that can be used in studies involving biofilm-specific polysaccharides is discussed.

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Multiple facet supported alumina nanowires are produced very efficiently in a very short time via high field anodization; upon modification with perfluorosilane, the surface becomes super-repellent towards a broad range of liquids, which includes (salted) water, water emulsion, common organic liquids like glycerol and alkanes, and a variety of lubrication oils including ionic liquids, poly(alpha-olefin), polydimethylsiloxane oils etc.

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High-quality Bi 2 S 3 and Sb 2 S 3 nanorods on a large scale were successfully synthesized by the solvothermal treatment of a novel kind of single-source precursors (SSPs), metal di-n-octyl-dithiophosphates (M[S 2 P-(OC 8 H 17 ) 2 ] 3 , M ) Bi, Sb). The X-ray powder diffraction (XRD) patterns show that both of these products belong to the orthorhombic M 2 S 3 phase. The experimental results show that the Bi 2 S 3 nanorods can be easily prepared in air at g140 °C for 5 h in the presence of oleylamine. Transmission electron microscopy (TEM) images show the rodlike appearance of Bi 2 S 3 with a diameter of 7-21 nm and length of several hundred nanometers under the various reaction conditions. The effects of reaction parameters, such as reaction time, temperature, and concentration of the precursor, on the growth of nanorods were discussed in detail. The mechanism of the formation process of the nanorods was proposed. We also demonstrate that this method can be extended to the synthesis of Sb 2 S 3 nanorods, which have an average diameter in the range of 45 nm and a length in the range of 1 µm. The optical absorption experiment shows that these nanorods are semiconductor with bandwidth E g ) 1.67 eV for Bi 2 S 3 and 1.76 eV for Sb 2 S 3 , both near to the optimum for photovoltaic conversion, suggesting these nanorods could be used in solar energy and photoelectronic applications.

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This article describes a strategy to fabricate a conducting polymer and complementary gold microstructures through selective electrodeposition and wet chemical etching on a chemically tethered polymer brush template that is prepared by surface‐initiated atomic transfer radical polymerization (ATRP) and subsequent photopatterning. The polymer brush acts as a sufficient insulating barrier and thus the polypyrrole (PPy) can be grown from the exposed area of the polymer brush template. Different polymer brushes provide different protection actions in selective etching, which is utilized to generate complementary (negative or positive) gold pattern on a single template in different manners.

High-quality faceted nanocrystals and triangular nanoplates of copper sulfide have been successfully synthesized by using the single source precursor method in the presence of oleylamine. The obtained faceted copper sulfide nanocrystals have an average size of 9.8 ± 0.3 nm, showing the regularly hexagonal closely packed nanostructure. The resulting triangular copper sulfide nanoplates have an average side length of 12.3 ± 0.6 nm, thickness of 0.8 nm, forming the six-leave flowerlike nanostructure due to their size uniformity. We also demonstrate that the shape, size, and even the phase forms of copper sulfide nanocrystals can be controlled systematically by adjusting certain reaction parameters, such as the carbon number of the substitute alkyl (n), the reaction temperature, and the concentration of the precursor.