Abstract: This technology is a method and apparatus for the semi-continuous measurement of the concentration of constituents of airborne particles which couples a laminar flow, water condensation particle collector to a microfluidic device for assay of particle chemical composition by electrophoresis. The technology has been used for the assay of sulfates, nitrates, chlorides, and organic acids contained in fine and submicrometer atmospheric particles. For these compounds the apparatus and method described is capable of one-minute time resolution at concentrations at the level of micrograms of analyte species per cubic meter of air. Extension to other analytes is possible.

Abstract: This technology is a method and apparatus for the semi-continuous measurement of the concentration of constituents of airborne particles which couples a laminar flow, water condensation particle collector to a microfluidic device for assay of particle chemical composition by electrophoresis. The technology has been used for the assay of sulfates, nitrates, chlorides, and organic acids contained in fine and submicrometer atmospheric particles. For these compounds the apparatus and method described is capable of one-minute time resolution at concentrations at the level of micrograms of analyte species per cubic meter of air. Extension to other analytes is possible.

Abstract: Construction and characterization of microfabricated recessed disk microelectrodes (RDMs) of 14 and 55 ?m diameter are reported. The work reported here makes several new contributions to the current literature on microfabricated RDMs. Hybrid blamers were constructed by fusion of vesicles of dimyristoylphosphatidyl choline (DMPC), which forms the top layer, with ethanol-rinsed SAMs of hexadecanethiol on gold, which form the bottom layer. Gramicidin A was included in the modifying solutions to incorporate it into hybrid blamers.

Abstract: Microcavities and micropores that are microscopic (<1 mm) in width and depth and contain any number of individually-addressable electrodes, separated by insulators, along the walls of each cavity. The conducting materials, and the insulator materials can be deposited alternately onto a starting substrate, which is typically an oxidized silicon wafer or polyimide film, but may be any substrate that shows good adhesion to the materials layered on it. The cavities are etched through these layers, perpendicular to the plane of the substrate, exposing the layers at their edges. Pores may be carved entirely through the device.

Abstract: Construction and characterization of microfabricated recessed disk microelectrodes (RDMs) of 14 and 55 &mgr;m diameter are reported. The work reported here makes several new contributions to the current literature on microfabricated RDMs. Hybrid blamers were constructed by fusion of vesicles of dimyristoylphosphatidyl choline (DMPC), which forms the top layer, with ethanol-rinsed SAMs of hexadecanethiol on gold, which form the bottom layer. Gramicidin A was included in the modifying solutions to incorporate it into hybrid blamers.