Directory: Faculty
 |
Henry S. WhiteANALYTICAL CHEMISTRYDistinguished Professor and Chair B.S., University of North Carolina, 1978 Phone: (801) 585-6256 Office: B423 HEB-S Email: white@chem.utah.edu |
Activities & Awards
- W.W. Epstein Outstanding Educator Award, U of Utah, 2007
- Grahame Award of the Electrochemical Society, 2005
- President, Society of Electroanalytical Chemistry, 2003-2005
- Associate Editor, Journal of the American Chemical Society
- ACS Analytical Division Award in Electrochemistry, 2004
- University of Utah, Distinguished Research Award, 2004
- Students Choice Teaching Award, Associated Students of the U of Utah, 2003
- Faraday Medal, Royal Society of Chemistry, London, 2002
- Professeur Invité de l’Ecole Normale Supérieure, Paris, France, 2002
- Chair, Gordon Research Conference on Electrochemistry, 2002
- Reilley Award of the Society of Electroanalytical Chemistry, 2000
- Shell Chair of Chemical Engineering and Materials Science, U of Minnesota, 1992
- Office of Naval Research Young Investigator Award in Chemistry, 1987
- McKnight Land-Grant Professorship, University of Minnesota, 1987
- Shell Faculty Career Initiation Award, 1985
- Gilbert H. Ayres Award, University of Texas, 1982
Research Interests
My colleagues and I are engaged in both experimental and theoretical aspects of electrochemistry, with diverse connections to analytical, biological, physical, and materials chemistry. Much of our current research is focused on electrochemistry in microscale and nanoscale domains.
Electrochemistry in Nanoscale Domains. Methods of electrode fabrication are being developed that allow voltammetric analyses of very small numbers of molecules. We have also recently developed the "glass nanopore electrode", a Pt disk electrode embedded at the bottom of a conical shaped pore, the circular orifice of the pore having nanometer dimensions. The steady-state flux of molecules to this electrode is limited by transport through the orifice, a very useful characteristic in studying transport in nanometer-diameter pores. Chemical modification of the pore walls introduces chemical-selective transport for sensing applications. The Pt can also be removed to create a "glass nanopore membrane", which is well suited for nanoparticle analysis and as a robust support for lipid bilayers and protein ion channels.
Coulomb Transport in Ultrathin-Layer Electrochemical Cells. Investigations of electrochemical cells comprising two electrodes separated by ultra-thin (~10 nm) layers of electrolyte have demonstrated that overlap of the electrical double layers results in molecular transport being driven by the surface charge of the electrodes, a phenomenon we refer to as "coulomb transport." The influence of coulomb transport on the characteristics of nanometer-scale electrochemical cells is being investigated for applications in batteries and chemical sensors.
Iontophoretic Transport Through Skin. Electric field-induced molecular transport through human skin is currently being investigated as a means of drug administration. Human skin is a very complex, heterogeneous membrane, and molecular transport through it is poorly characterized. Our current effort focuses on developing experimental methods to determine the physiological structures in skin that act as molecular transport pathways. Scanning electrochemical microscopy has been developed in our laboratory to visualize molecular transport in biological membranes.
Magnetic Field Effects on Electrochemical Reactions . Measurements are made using ultramicroelectrodes to enhance the Lorentzian and gradient forces that developed at the electrode/electrolyte interface during electron-transfer processes. Solution-phase ion-trapping and focusing techniques for analytical applications are also being developed.
Selected Publications
- Yue Zhao, Gangli Wang, and Henry S. White, “Double-Layer Controlled Transport Limited Responses at Pt Nanodisk Electrodes Shrouded by Amine-Modified Glass,” submitted.
- Henry S. White, Andreas Bund, “The mechanism of electrostatic gating at conical glass nanopore electrodes,” submitted.
- Ryan J. White and Henry S. White “Electrochemistry in Nanometer-Wide Electrochemical Cells,” Langmuir, 24, 2850-2855 (2008).
- Eric N. Ervin, Ryuji Kawano, Ryan J. White, and Henry S. White “Simultaneous Alternating and Direct Current Readout of Protein Ion Channel Blocking Events using Glass Nanopore Membranes,” Anal. Chem., 80, 2069 – 2076 (2008).
- Henry S. White and Andreas Bund, “Ion current rectification at nanopores in glass membranes,” Langmuir, 24, 2212-2218 (2008).
- Ryan J. White, Eric N. Ervin, Tinglu Yang, Xin Chen, Susan Daniel, Paul S. Cremer, and Henry S. White, “Single Ion-Channel Recordings using Glass Nanopore Membranes,” J. Am. Chem. Soc., 129, 11766-11775 (2007).
- Ryan J. White and Henry S White, “Influence of Electrophoresis Waveforms in Determining Stochastic Nanoparticle Capture Rates and Detection Sensitivity,” Anal. Chem., 79, 6334-6340 (2007).
- Eric N. Ervin, Ryan J. White, Treggon G. Owens, John M. Tang, and Henry S. White “AC Conductance of Transmembrane Protein Channels. The Number of Ionized Residue Mobile Counter-ions at Infinite Dilution,” J Phys Chem., 111, 9165-9171 (2007).
- Jun Ho Shim, Juneho Kim, Geun Sig Cha, Hakhyun Nam, Ryan J. White, Henry S. White, and Richard B. Brown, “Glass Nanopore-Based Ion-Selective Electrodes,” Anal. Chem., 79, 3568-3574 (2007).
- Gangli Wang, Andrew K. Bohaty, Ilya Zharov, and Henry S. White “Photon Gated Transport at the Glass Nanopore Electrode,” J. Am. Chem. Soc., 128, 13553-13558 (2006).
- Bo Zhang, Jeremy Galusha, Peter G. Shiozawa, Gangli Wang, Adam Johan Bergren, Ronald M. Jones, Ryan J. White, Eric N. Ervin, Chris C. Cauley, and Henry S. White, “A Bench-Top Method of Fabricating Glass-Sealed Nanodisk Electrodes, Glass Nanopore Electrodes, and Glass Nanopore Membranes of Controlled Size,” Anal. Chem, 79, 4778-4787, (2007).
- Ryan J. White, Bo Zhang, Susan Daniel, John Tang, Eric N. Ervin, Paul S. Cremer, and Henry S. White, “Ionic Conductivity of the Aqueous Layer Separating a Lipid Bilayer Membrane and a Glass Support,” Langmuir, 22, 10777-10783 (2006).