AVS 53rd International Symposium
    Applied Surface Science Monday Sessions
       Session AS+BI+NS+NM-MoM

Paper AS+BI+NS+NM-MoM4
XPS Analysis of Arenes and Proteins on Gold Substrates Attached by Electrochemical Reduction of Aryldiazonium Salts

Monday, November 13, 2006, 9:00 am, Room 2005

Session: Organic Surface Modification and Nanoscale Chemical Patterning
Presenter: J.L. Fenton, University of New Mexico
Authors: J.L. Fenton, University of New Mexico
S.M. Dirk, Sandia National Labs
D. Wheeler, Sandia National Labs
J.E. Fulghum, University of New Mexico
Correspondent: Click to Email
The properties of most materials can be altered by the attachment of molecules to their surface. Recent work has shown that diazonium salts can be used to attach aryl compounds to metal and semiconductor surfaces including silver, iron, platinum, silicon, and glassy carbon. Diazonium salts can be electrochemically reduced in acetonitrile leading to the attachment of aryl groups to the surface of a substrate. The attachment of aryl compounds using diazonium salts developed in our work, allows one to attach aryl compounds with different organic moieties onto metal substrates including gold. Aryl organic layers can be made of different thicknesses, and stacked structures can be created by alternating layers of molecules. This work is then expanded upon to attach proteins to metal surfaces. This approach provides a methodology to generate arrayed proteins on electrode arrays without the use of microfluidic methods such as ink jetting etc. The development of protein arrays can often provide high-throughput, quantitative measurement of receptor-ligand complexation giving an understanding of protein function, modification, and regulation. X-ray photoelectron spectroscopy (XPS) is used to deduce the different types of chemistries in single molecule samples, stacked structures, and surface tethered proteins. Angle resolved XPS is used to determine the relative location of each molecule in the stacked structures and possible orientation of proteins as well as to deduce the existence of azo linkages.