Atomic force microscopy at high temperature resolution (DeltaT < or approximately 0.1 K) provided a quantitative structural calorimetry of the transition from the fluid (Lalpha)- to the gel (Pbeta')-phase of supported dimyristoylphosphatidylcholine bilayers. Besides a determination of the main transition temperature (T0) and the van't Hoff transition enthalpy (DeltaHvH), the structural analysis in the nm-scale at T close to T0 of the ripple phase allowed an experimental estimation of the area of cooperative units from small lipid domains. Thereby, the corresponding transition enthalpy (DeltaH) of single molecules could be determined. The lipid organization and the corresponding parameters T0 and DeltaHvH (DeltaH) were modulated by heptanol or external Ca2+ and compared with physiological findings. The size of the cooperative unit was not significantly affected by the presence of 1 mM heptanol. The observed linear relationship of DeltaHvH and T0 was discussed in terms of a change in heat capacity.

Brushing up: Poly(N‐isopropylacrylamide) micro‐ and nanostructures can be grown on a gold substrate by grafting the polymer brush from an initiator‐coated surface. The dependence of the brush height on the density of the initiator (controlled by the electron‐beam doses) allows spatially defined polymer patterns with varying heights and unique surface topographies (see image) to be created in a single step.

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The line-scan mode is applied in aqueous suspensions of NHS-nanogold and NHS -nanogold-lysozyme conjugates to generate tip-induced linelike pattern with a width in the nanometer scale. With increasing ionic strength the spontaneous adsorption of the particles to the mica surface can be reduced. The reduction causes an increase in the processing time, which is necessary to form a continuous line composed of the respective particles. The line width increases with increasing loading force. For NHS-nanogold, a minimal line width of about 40 nm could be achieved. The results were used to connect two opposite macroscopic gold contacts about 5 µm apart by a line of NHS-nanogold, which appeared to be of continuous structure down to the nanometer scale, according to the corresponding topography.

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