The adhesion of microorganisms on a patterned polyurethane surface was studied simultaneously online and in situ with a quartz crystal microbalance (QCM) and an atomic force microscope (AFM). The specific interaction between Saccharomyces cerevisiae cells and their fingerprints formed by molecular imprinting results in a typical Sauerbrey behaviour, when adhesion events are observable with an AFM. The sensor response due to adsorption of Gram positive Leuconostoc oenus, however, shows non-Sauerbrey behaviour. Bacteria, naturally being smaller than yeast cells, were 'invisible' to liquid phase AFM-measurements, which is due to a weaker surface interaction. Thus, AFM measurements give a hint for unusual frequency enhancements in QCM microorganism measurements.

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Well-dispersed gold nanodumbbells (GNDs) in an aqueous phase have been successfully fabricated by an electrochemical method using a micelle template formed by two surfactants with the addition of acetone solvent during electrolysis, the primary surfactant being cetyltrimethylammonium bromide (CTABr) and the cosurfactant being tetradecyltrimethylammonium bromide (TTABr). The role of acetone solvent is found to change the gold nanoparticles' shape from a rod to a dumbbell. The shape of the GNDs is fatter at the two ends and thinner in the middle section. The GNDs have been determined to be pure gold with a single-crystalline face-centred cubic (FCC) structure from selected area electron diffraction (SAED) patterns. Morphology features of GNDs in cross-section have also been investigated by dark field (DF) transmission electron microscopy (TEM) images. These GNDs exhibit octagonal structure in cross-section and an aspect ratio of around 3.

The barium titanate (BaTiO3) nanoparticles with novel dendrite-like structures have been successfully fabricated via a simple coprecipitation method, the so-called BaTiO3nanodendrites (BTNDs). This method was remarkable, fast, simple, and scalable. The growth solution is prepared by barium chloride (BaCl2), titanium tetrachloride (TiCl4), and oxalic acid. The shape and size of BaTiO3depend on the amount of added BaCl2solvent. To investigate the influence of amount of BaCl2on BTNDs, the amount of BaCl2was varied in the range from 3 to 6 mL. The role of BaCl2is found to have remarkable influence on the morphology, crystallite size, and formation of dendrite-like structures. The thickness and length of the central stem of BTND were ~300 nm and ~20 μm, respectively. The branchings were found to occur at irregular intervals along the main stem. Besides, the formation mechanism of BTND is proposed and discussed.

In this study, silica-coated silver nanoparticles (SSNPs) with a core-shell structure are successfully fabricated using a simple sol-gel method without using primer, surfactant or surface modification of core. To investigate the influence of ammonical silver nitrate (AgNO 3 ) on the synthesis of SSNPs, the amount of an aqueous solution of AgNO 3 was varied in the range from 3 to 12 mL. It was found that the thickness of silver shell could be formed in the range of ∼20 to ∼60 nm, and the UV-vis optical absorption measurement revealed a pronounced red-shift of the surface plasmon resonance (SPR) band from 442 to 516 nm.