Preferential adsorption of horse heart cytochrome c on nanometer-scale domains of a phase-separated binary self-assembled monolayer of 3-mercaptopropionic acid and 1-hexadecanethiol on Au(111)

Cytochrome c preferentially adsorbs on the nanometer-scale 3-mercaptopropionic acid (MPA) domains of the phase-separated binary self-assembled monolayers (SAMs) of MPA and 1-hexadecanethiol on Au(111), which has been imaged by scanning tunneling microscopy (STM). The amount of the adsorbed cytochrome c estimated by STM increases with increasing the ratio of MPA of the binary SAMs and agrees well with that estimated by cyclic voltammetry of the cylochrome c-adsorbed Au(111).