Molecular-scale structures of the surface and hydration shell of bioinert mixed-charged self-assembled monolayers investigated by frequency modulation atomic force microscopy.

ABSTRACT: We studied the surface structure and hydration structure of a bioinert mix-charged self-assembled monolayer (MC-SAM) comprised of sulfonic acid (SA)- and trimethylamine (TMA)-terminated thiols in liquid by frequency modulation atomic force microscopy (FM-AFM) at a molecular-scale. The TMA end groups showed a highly-ordered rectangular arrangement on a gold substrate in phosphate buffer saline (PBS). Highly structured water was observed at the interface of the MC-SAM and PBS, whereas a less structured hydration structure was observed on bioactive SAMs such as those with OH- and COO- terminal groups. Differences in surface and interface structures between the bioactive and bioinert SAMs suggest that the highly structured water at the bipolar MC-SAM surface works as a physical barrier to prev

SUBMITTER: Araki Y 

PROVIDER: S-EPMC9082155 | biostudies-literature | 2018 Jul

REPOSITORIES: biostudies-literature