Construction of molecular probe on Au surface for detecting the tri-strand β-sheet structure

The molecular probes were brought up on the mixed self-assembled monolayer (SAM) of propanethiol and cysteamine on Au (111) surface for detecting the tri-strand β-sheet structured oligo-peptides. The detecting tri-strand β-sheet structured amyloid plaques using various mimic systems have been investigated since the fact that Alzheimer disease is caused by the β-sheet amyloid is elucidated. In this study, several di-urea materials were synthesized in order to detect the mimic tri-strand β-sheet structure, which consist of di-urea and assembled molecular probes. The characterization of the mixed self-assembled monolayer, and molecular probes were carried out by ellipsometry, contact angle goniometry, and scanning tunneling microscopy (STM). The average distribution of molecular domain of active amine-terminated cysteamine monolayer was estimated indirectly using contact angle measurement.