A new experiment for use in introductory nanotechnology courses is described. This experiment allows students to fabricate metallic wires with microscale lateral dimensions and nanoscale vertical dimensions. Fabrication occurs in the capillaries of polydimethylsiloxane (PDMS) stamps modified with hydrophilic polymers. This experiment provides students with an opportunity to conduct templateassisted electrodeposition of micro-and nanomaterials, utilizing a reusable template instead of the commonly used porous, anodic alumina oxide (AAO) membranes that require dissolution to examine the wires. Fabrication of the metal wires is accomplished via the reduction of metal cations in the channels of modified PDMS stamps. In addition, this experiment introduces students to characterization using scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and atomic-force microscopy (AFM). The microscale dimensions of the silver wires accommodate imaging with optical microscopy for institutions possessing limited characterization capabilities.

An improved photo-cured membrane selective to calcium was developed based on the calcium bis[4-(l , I ,3,3-tetramethylbutyl)phenyl] phosphate ionophore and incorporates the lipophilic additive, potassium tetrakis(pchloropheny1)borate. The calcium electrode exhibited a hyper-Nernstian response of 31.0 mV change per activity decade and a log-linear range between 1 x lo-' to 0. I M in pure calcium chloride solution, in steady-state mode. The calcium electrode was fast responding, reaching 90% of steady-state value in 5 s making it ideal for flow injection measurements. The photo-cured electrode can measure calcium in a high perchlorate background, and was used to determine the total calcium level in full cream milk that was digested by a nitric/perchloric acid mixture. The results obtained were in good agreement with atomic absorption spectroscopy measurements.

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