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Title: Proline Adsorption on TiO2(1 1 0) Single Crystal Surface: A Study by High Resolution Photoelectron Spectroscopy

Abstract

The surface chemistry and binding of dl-proline were investigated on the oxidised (stoichiometric) and reduced (sub-stoichiometric) TiO2(1 1 0) single crystal surfaces. TiO2 was chosen as the substrate as it best represents the surface of a biomedical implant, which bio-molecules interact with during the healing of bone/teeth fractures (molecular recognition). High resolution X-ray photoelectron spectroscopy (HR-XPS) studies of the C1s and N1s regions revealed that dl-proline is present in two forms (dissociated and zwitterionic) on the oxidised TiO2 surface. On TiO2(1 1 0) surfaces reduced by Ar+ sputtering, a significant increase in the amount of zwitterionic proline at the surface was detected when compared with the oxidised surface. Study of the temperature effect showed that in both cases the zwitterionic structure was the less stable structure. The reason for its relative instability appears to be thermodynamic.

Authors:
; ; ; ;
Publication Date:
Research Org.:
Brookhaven National Laboratory (BNL) National Synchrotron Light Source
Sponsoring Org.:
Doe - Office Of Science
OSTI Identifier:
959760
Report Number(s):
BNL-82746-2009-JA
Journal ID: ISSN 0039-6028; SUSCAS; TRN: US201016%%904
DOE Contract Number:
DE-AC02-98CH10886
Resource Type:
Journal Article
Resource Relation:
Journal Name: Surface Science; Journal Volume: 601; Journal Issue: 24
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ADSORPTION; CHEMISTRY; FRACTURES; HEALING; INSTABILITY; MONOCRYSTALS; PHOTOELECTRON SPECTROSCOPY; PROLINE; RESOLUTION; SPUTTERING; SUBSTRATES; TEMPERATURE DEPENDENCE; X-RAY PHOTOELECTRON SPECTROSCOPY; SURFACES; national synchrotron light source

Citation Formats

Fleming,G., Adib, K., Rodriguez, J., Barteau, M., and Idriss, H. Proline Adsorption on TiO2(1 1 0) Single Crystal Surface: A Study by High Resolution Photoelectron Spectroscopy. United States: N. p., 2007. Web. doi:10.1016/j.susc.2007.06.074.
Fleming,G., Adib, K., Rodriguez, J., Barteau, M., & Idriss, H. Proline Adsorption on TiO2(1 1 0) Single Crystal Surface: A Study by High Resolution Photoelectron Spectroscopy. United States. doi:10.1016/j.susc.2007.06.074.
Fleming,G., Adib, K., Rodriguez, J., Barteau, M., and Idriss, H. Mon . "Proline Adsorption on TiO2(1 1 0) Single Crystal Surface: A Study by High Resolution Photoelectron Spectroscopy". United States. doi:10.1016/j.susc.2007.06.074.
@article{osti_959760,
title = {Proline Adsorption on TiO2(1 1 0) Single Crystal Surface: A Study by High Resolution Photoelectron Spectroscopy},
author = {Fleming,G. and Adib, K. and Rodriguez, J. and Barteau, M. and Idriss, H.},
abstractNote = {The surface chemistry and binding of dl-proline were investigated on the oxidised (stoichiometric) and reduced (sub-stoichiometric) TiO2(1 1 0) single crystal surfaces. TiO2 was chosen as the substrate as it best represents the surface of a biomedical implant, which bio-molecules interact with during the healing of bone/teeth fractures (molecular recognition). High resolution X-ray photoelectron spectroscopy (HR-XPS) studies of the C1s and N1s regions revealed that dl-proline is present in two forms (dissociated and zwitterionic) on the oxidised TiO2 surface. On TiO2(1 1 0) surfaces reduced by Ar+ sputtering, a significant increase in the amount of zwitterionic proline at the surface was detected when compared with the oxidised surface. Study of the temperature effect showed that in both cases the zwitterionic structure was the less stable structure. The reason for its relative instability appears to be thermodynamic.},
doi = {10.1016/j.susc.2007.06.074},
journal = {Surface Science},
number = 24,
volume = 601,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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