Surface composition of mixed self-assembled monolayers on Au by infrared attenuated total reflection spectroscopy

Angelo Tricase, Davide Blasi, Alessandro Favia, Angela Stefanachi, Francesco Leonetti, Giuseppe Colafemmina, Luisa Torsi, Gaetano Scamarcio*

*Corresponding author for this work

Research output: Contribution to journalArticleScientificpeer-review

5 Citations (Scopus)
33 Downloads (Pure)

Abstract

Self-assembled monolayers (SAMs) of N-(2-hydroxyethyl)-3-mercaptopropanamide (NMPA) were synthesized directly on the surface of electron-beam evaporated Au films, starting from 3-mercaptopropionic acid (3MPA) via ethyl-3-(3-dimethylamino-propyl)carbodiimide/N-hydroxysulfosuccinimide sodium salt (EDC/NHSS) coupling with ethanolamine hydrochloride. The influence on the reaction yield of the acidity of EDC/NHSS solutions (pH = 5.6 or 4.8) was assessed by exploiting the high surface sensitivity of infrared attenuated total reflection spectroscopy. The light-matter interaction was modeled in the framework of a matrix formalism considering the complete multi-layer sample structure. A comparison between the relative intensity of the main absorption bands, associated with amide I and carbonyl stretching of carboxylic acid or amide II vibrations, with a calibration curve obtained from the measurement of mixed 3MPA/NMPA SAMs, show that the more acid solution is 16% more efficient. This is mostly due to the higher protonation of the 3MPA.

Original languageEnglish
Article number149883
JournalApplied Surface Science
Volume559
DOIs
Publication statusPublished - 1 Sept 2021
MoE publication typeA1 Journal article-refereed

Keywords

  • Attenuated total reflection spectroscopy
  • Biofunctionalized interfaces
  • Self-assembled monolayers

Fingerprint

Dive into the research topics of 'Surface composition of mixed self-assembled monolayers on Au by infrared attenuated total reflection spectroscopy'. Together they form a unique fingerprint.

Cite this