Solution and Surface Characterization of DNA and Proteins

Abstract

A variety of experimental spectroscopic techniques complemented by theoretical calculations when appropriate were used to investigate DNA adlayers on surfaces and proteins in solution. The formation and characterization of DNA adlayers on gold and indium tin oxide surfaces were characterized along with subsequent surface DNA hybridization. Prior to the modification of indium tin oxide surfaces with DNA, the optical and electronic properties of this metal oxide, fluorine doped tin oxide and iridium oxide were investigated. The detection of DNA hybridization on indium tin oxide surfaces utilized gold nanoparticle labeled target ssDNA. Further work on gold surfaces was performed using infrared spectroscopy to detect sugar binding to a phenylboronic acid terminated self-assembled monolayer. The binding properties and stability of gold nanoparticles were investigated by characterizing citrate and bovine serum albumin binding to gold surfaces and the stability of particles stabilized by these molecules. The stability and folding kinetics of the three helix bundle protein, villin headpiece subdomain was also investigated in addition to a theoretical investigation of the vibrational Stark effect. Finally, a time resolved step scan FTIR spectrometer was implemented with five microsecond time resolution.