An electrochemical and surface plasmon resonance study of adsorption actions of DNA by Escherichia coli

In this work, we proposed an immobilization scheme targeting Escherichia coli bacterial cells onto gold surface utilizing polypeptide RGD's binding specificity to gold particles. Adsorption kinetics of extracellular Herring Sperm DNA on E. coli was then studied using electrochemical methods along with surface plasmon resonance spectroscopy through this immobilization scheme. The adsorption equilibrium constants of DNA adsorbing to E. coli from electrochemical method and surface plasmon resonance spectroscopy, were (5.596 +/- 0.462) x 105 Lmol(-1) and (1.24 +/- 0.361) x 105 Lmol(-1), accordingly. Importantly, this is the first study that used an electrochemical method to express the adsorptive action of DNA by E. coli. (C) 2014 Elsevier B.V. All rights reserved.