• Binghua Chai Department of Bioengineering, Box 355061, University of Washington, Seattle, WA 98195
  • Amrita G. Mahtani Department of Bioengineering, Box 355061, University of Washington, Seattle, WA 98195
  • Gerald H. Pollack Department of Bioengineering, Box 355061, University of Washington, Seattle, WA 98195



Earlier, we reported solute-free “exclusion zones” in aqueous media next to various metal surfaces. Here we explore the effect of connecting zinc, which ordinarily shows a large exclusion zone, to platinum, which ordinarily does not. We found the connecting the two metals diminished the exclusion zone next to zinc, while it increased the exclusion zone next to platinum. Disconnecting resulted in return to control values. These effects were largest when the metals were juxtaposed relatively closely, and became smaller with increasing separation. The underlying mechanisms are considered.


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