Electrochemical impedance spectroscopy of the interaction of STMpep9 with CDK2-expressing cell lysate. (a) EIS φ(ω) data for a gold surface functionalized with STMpep9 (orange circles) and following exposure to CDK2-expressing yeast lysate (blue circles). (b) As (a) but following exposure of STMpep9 to a CDK-free yeast lysate. (c) Data from (a) and (b) plotted as the phase shift (Δφ(ω)) for independent electrodes functionalized with STMpep9 and exposed to either a CDK2-expressing yeast lysate (blue line) or a CDK2-free lysate (orange line). The black line represents the Δφ(ω) of an STM-functionalized gold electrode following exposure to CDK2-expressing yeast lysate. A phase shift is only detectable upon exposure of STMpep9 to CDK2, indicating that yeast proteins neither interact nonspecifically with the peptide aptamers nor specifically or nonspecifically with the electrode surface.
Evans et al. Journal of Biology 2008 7:3 doi:10.1186/jbiol62