Abstract
The adsorption of histidine (His), and its peptide glycyl-glycyl-histidine (Gly-Gly-His), on Au(111) and Au(110) has been studied by soft X-ray photoelectron spectroscopy (XPS) and near edge X-ray absorption fine structure spectroscopy (NEXAFS) at the nitrogen and oxygen K-edges. The molecules were adsorbed on surfaces from acidic (pH ∼3) solution. The results are compared with our previous studies of the adsorption of histidine and its peptides on Au(111) deposited on Au(111) from neutral solutions. When deposited from acidic solution, His adsorbs as carboxylic and carboxylate forms on both Au(111) and Au(110) surfaces, whereas its peptide is present mainly in the carboxylic form. In contrast, both molecules deposited from neutral solution adsorbed mainly as carboxylates. The imino nitrogen atom of the imidazole ring plays a crucial role in the interaction with gold surfaces. The Au 4f core level shift indicates that a chemisorption rather than a physisorption process occurs.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
