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The adsorption of a range of organic molecules from toluene onto the oxidized surface of magnetronsputtered aluminium metal is studied using sessile drop water contact angle measurements. Molecules with different head group functionalities and various chain lengths are considered, including alkyl carboxylic acids, alkyl phosphonic acids, alkyl amines, alkyl trimethoxysilanes, alkyl trichlorosilanes and epoxy alkanes. Alkyl phosphonic and carboxylic acids are identified as readily forming the most wellpacked monolayers on the aluminium surface, whereas the others adsorb less well and the chlorosilanes polymerize as a result of combination with moisture to form a thick deposit. The high-adsorption-density monolayers of alkyl phosphonic and carboxylic acids were studied using polarization modulation infrared reflection-absorption spectroscopy (PM-IRRAS) and x-ray photoelectron spectroscopy (XPS): PM-IRRAS reveals relatively poorer ordering of the C 10 alkyl carboxylic acid monolayer compared with that formed from the phosphonic acid, and XPS data suggest that this is likely to relate to a lower ability to displace preadsorbed volatile organic compounds.

Essential oils with high antibiotic activity were incorporated into cellulose acetate natural polymer. By using the electrospinning technique, nanofibrous matrices were prepared to be used as effective antimicrobial wound dressings.

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We report the development of a method to determine the aqueous stability of self-assembled monolayers (SAMs) using the Wilhelmy plate dynamic contact angle (DCA) experiment. The DCA is measured in solutions over a range of pH values for alkyl carboxylic and alkyl phosphonic acid SAMs formed on magnetron-sputtered aluminum. The change in DCA on repeated immersion is used as a measure of the degradation of the SAMs by hydrolytic attack. The short and intermediate chain length alkyl acids are not stable in water of neutral pH, whereas molecules with the longest alkyl chains show considerably greater stability in neutral and both high and low pH solutions. The packing density inferred from the DCA and the contact angle hysteresis suggests the C18CO2H monolayer to be slightly less well packed than that of the C18P(=O)(OH)2; this is consistent with related friction force microscopy and infrared reflection absorption spectroscopy findings published elsewhere (Foster, T. T.; Alexander, M. R.; Leggett, G. J.; McAlpine, E. Langmuir 2006, 22, 9254-9259). The resistance of the SAMs to acid and alkaline environments is discussed in the context of aluminum oxide solubility, SAM packing density, and the resistance of the interfacial phosphate and carboxylate functionalities to different aqueous conditions.

Even if deeper examinations will be necessary in order to better clarify the mechanisms at the base of the documented effects, nanoceria demonstrated a significant potential as pharmacological agent in the treatment of neurological disorders.