Articles by Tran T. Doan in JoVE
Synthesis, Assembly, and Characterization of Monolayer Protected Gold Nanoparticle Films for Protein Monolayer Electrochemistry Tran T. Doan1, Michael H. Freeman2, Adrienne R. Schmidt2, Natalie D. T. Nguyen2, Michael C. Leopold1 1Department of Chemistry, Gottwald Center for the Sciences, University of Richmond, 2Department of Biochemistry and Molecular Biology, Gottwald Center for the Sciences, University of Richmond Alkanethiolate stabilized gold colloids known as monolayer protected clusters (MPCs) are synthesized, characterized, and assembled into thin films as an adsorption interface for protein monolayer electrochemistry of simple redox protein like Pseudomonas aeruginosa azurin (AZ) and cytochrome c (cyt c).
Other articles by Tran T. Doan on PubMed
Electrochemical Analysis of Azurin Thermodynamic and Adsorption Properties at Monolayer-protected Cluster Film Assemblies - Evidence for a More Homogeneous Adsorption Interface Journal of Colloid and Interface Science. Dec, 2010 | Pubmed ID: 20825950 Thermodynamic and adsorption properties of protein monolayer electrochemistry (PME) are examined for Pseudomonas aeruginosa azurin (AZ) immobilized at an electrode modified with a networked film of monolayer-protected clusters (MPCs) to assess if nanoparticle films of this nature offer a more homogeneous adsorption interface compared to traditional self-assembled monolayer (SAM) modified electrodes. Specifically, electrochemistry is used to assess properties of surface coverage, formal potential, peak broadening, and electron transfer (ET) kinetics as a function of film thickness. The modification of a surface with dithiol-linked films of MPCs (Au(225)C6(75)) provides a more uniform binding interface for AZ that results in voltammetry with less peak broadening (120-130mV). Improved homogeneity of the MPC interface for protein adsorption is confirmed by atomic force microscopy imaging that shows uniform coverage of the gold substrate topography and by electrochemical analysis of film properties during systematic desorption of AZ, which indicates a more homogeneous population of adsorbed protein at MPC films. These results suggest MPC film assemblies may be used in PME to provide greater molecular level control of the protein adsorption interface, a development with applications for strategies to study biological ET processes as well as the advancement of biosensor technologies.