A simple two-step plasmachemical methodology is outlined for the fabrication of microcondensor surfaces. This comprises the creation of a superhydrophobic background followed by pulsed plasma deposition of a hydrophilic polymer array. Microcondensation efficiency has been explored in terms of the chemical nature of the hydrophilic pixels and their dimensions. These results are compared to the hydrophilic-hydrophobic pattern present on the Stenocara beetle's back, which is used by the insect to collect water in the desert. Potential applications include fog harvesting, microfluidics, and biomolecule immobilization.

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Repetitive bursts of continuous wave plasma polymerization on the minute time scale are found to lead to the deposition of well-defined polymeric nanospheres. This unique mode of film growth is attributed to a high level of monomer replenishment in combination with minimal secondary reaction processes (e.g., fragmentation, cross-linking, and etching). In the case of the 1H,1H,2H,2H-perfluorooctyl acrylate precursor, high contact angle (super-hydrophobic) surfaces are produced by this method.

The surfaces of standard untreated polystyrene cell culture dishes have been oxidatively modified for up to 8 min exposure time using an ultraviolet ozone treater in order to promote cell adhesion. Surface oxygen chemisorption and topographical modification has been characterized using monochromatic X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM), respectively. The oxidation process is shown to proceed at low exposure times (<60 s) via the formation of CsOR groups, although some R2CdO and RO-CdO groups are also formed. At longer treatments, RO-CdO groups become the dominant species, although the other groups are also present. The maximum level of oxygen reached is 36 atomic %. Some of the oxygen present at surfaces treated at times of >60 s is in the form of loosely bound low molecular weight oxidized material (LMWOM) which is produced by oxidative scission of the PS backbone. Water washing leads to a reduction in surface oxygen content mainly by the removal of ROsCdO and R2CdO functional groups. The residual stable oxygen levels, which can be introduced, are approximately 20-25 atomic %. Surface chemistry changes are accompanied by the formation of surface spikes which are about 30 nm high and 300-400 nm wide. A correlation between treatment time/oxygen level and overall roughness is observed. The effect of washing upon the topography is to slightly increase the surface roughness, although not to a significant degree. The attachment kinetics of adhesion for Chinese hamster ovary cells show that adhesion occurs much more rapidly for oxidized surfaces than for untreated control materials. A direct correlation between the levels of oxidation and the rate of cell adhesion is demonstrated.