Gas storage and gas separation using porous solids are important technologies that have attracted great attention because of their environmental and energetic applications. Highly porous materials, such as zeolites, silicate, and carbonbased materials, [1] have long-established specific applications. The key for new applications is the development of new frameworks. Advances in gas sorption capacities were achieved through the synthesis of materials such as metalorganic frameworks (MOFs), organic polymers, and microporous organic crystals.[2] Recently, crystals formed by dipeptides were tested as adsorbents [3] with significant results in hydrogen absorption and methane purification from carbon dioxide.

We report on the self-spreading behavior of a supported lipid bilayer passing through a sub-100-nm gap (nanogap). For this purpose, a device with a nanogap in a microchannel on a silicon substrate was designed and fabricated by electron beam lithography and photolithography. Fluorescence images of the lipid bilayer labeled with dye-conjugated lipids were observed by using a confocal laser scanning microscope. The time evolution of the self-spreading lipid bilayer passing through the nanogap was investigated at first. In the device, the lipid bilayer successfully passed through the nanogap without any stagnation. An analysis of the velocity of an advancing lipid bilayer showed no significant effect before or after passage though the nanogap. The effects of dye-conjugated lipid molecules and the size of the nanogap on the self-spreading behavior were examined next. We observed an abrupt decrease in the fluorescence intensity in the vicinity of the nanogap with Texas Red-DHPE and fluorescein-DHPE. It was revealed that the decrease depends on nanogap size as well as bulkiness of the dye molecule. The results suggest that bulkier dye molecules experience interference when they pass through narrower nanogaps.

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Nitric oxide (NO) is an endogenously produced molecule that has been implicated in several wound healing mechanisms. Its topical delivery may improve healing in acute or chronic wounds. In this study an antimicrobial peptide was synthesized which self-assembled upon a pH shift, forming a hydrogel. The peptide was chemically functionalized to incorporate a NO-donor moiety on lysine residues. The extent of the reaction was measured by ninhydrin assay and the NO release rate was quantified via the Griess reaction method. The resulting compound was evaluated for its antimicrobial activity against Escherichia coli, and its effect on collagen production by fibroblasts was assessed. Time-kill curves point to an initial increase in bactericidal activity of the functionalized peptide, and collagen production by human dermal fibroblasts when incubated with the NO-functionalized peptide showed a dose-dependent increase in the presence of the NO donor within a range of 0–20 μM.