Abstract
Two-dimensional infrared spectroscopy is a powerful tool for studying molecular structure and kinetics. However, standard ways of implementing the technique are not amenable to samples with high optical densities. In this paper, we demonstrate that a shaper-based automated 2D IR spectrometer largely compensates for most of the distortions caused by high optical densities. By comparing a series of 2D IR spectra collected with varying concentrations and sample thicknesses, we find that high quality 2D IR spectra can be obtained at optical densities of >1.2 when these spectra are collected using a pulse shaping method recently developed in our lab. Furthermore, distortions due to high OD primarily appear along the pump axis and are largely absent along the probe axis. Using this knowledge, we have applied our approach to study a high optical density sample of a truncated form of the human islet amyloid peptide that is involved in Type 2 diabetes. Our methodology promises to aid in the interpretation of 2D IR lineshapes for systems where the optical density cannot be controlled, such as in protein folding or chemical reactions where large changes in optical density occur during the kinetics.
| Original language | English |
|---|---|
| Pages (from-to) | 136-142 |
| Number of pages | 7 |
| Journal | Vibrational Spectroscopy |
| Volume | 50 |
| Issue number | 1 |
| DOIs | |
| Publication status | Published - 2009 May 26 |
| Externally published | Yes |
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Keywords
- 2D IR spectroscopy
- Infrared spectroscopy
- Optical density
- Pulse shaping
ASJC Scopus subject areas
- Spectroscopy
Cite this
Automated 2D IR spectrometer mitigates the influence of high optical densities. / Xiong, Wei; Strasfeld, David B.; Shim, Sang-Hee; Zanni, Martin T.
In: Vibrational Spectroscopy, Vol. 50, No. 1, 26.05.2009, p. 136-142.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Automated 2D IR spectrometer mitigates the influence of high optical densities
AU - Xiong, Wei
AU - Strasfeld, David B.
AU - Shim, Sang-Hee
AU - Zanni, Martin T.
PY - 2009/5/26
Y1 - 2009/5/26
N2 - Two-dimensional infrared spectroscopy is a powerful tool for studying molecular structure and kinetics. However, standard ways of implementing the technique are not amenable to samples with high optical densities. In this paper, we demonstrate that a shaper-based automated 2D IR spectrometer largely compensates for most of the distortions caused by high optical densities. By comparing a series of 2D IR spectra collected with varying concentrations and sample thicknesses, we find that high quality 2D IR spectra can be obtained at optical densities of >1.2 when these spectra are collected using a pulse shaping method recently developed in our lab. Furthermore, distortions due to high OD primarily appear along the pump axis and are largely absent along the probe axis. Using this knowledge, we have applied our approach to study a high optical density sample of a truncated form of the human islet amyloid peptide that is involved in Type 2 diabetes. Our methodology promises to aid in the interpretation of 2D IR lineshapes for systems where the optical density cannot be controlled, such as in protein folding or chemical reactions where large changes in optical density occur during the kinetics.
AB - Two-dimensional infrared spectroscopy is a powerful tool for studying molecular structure and kinetics. However, standard ways of implementing the technique are not amenable to samples with high optical densities. In this paper, we demonstrate that a shaper-based automated 2D IR spectrometer largely compensates for most of the distortions caused by high optical densities. By comparing a series of 2D IR spectra collected with varying concentrations and sample thicknesses, we find that high quality 2D IR spectra can be obtained at optical densities of >1.2 when these spectra are collected using a pulse shaping method recently developed in our lab. Furthermore, distortions due to high OD primarily appear along the pump axis and are largely absent along the probe axis. Using this knowledge, we have applied our approach to study a high optical density sample of a truncated form of the human islet amyloid peptide that is involved in Type 2 diabetes. Our methodology promises to aid in the interpretation of 2D IR lineshapes for systems where the optical density cannot be controlled, such as in protein folding or chemical reactions where large changes in optical density occur during the kinetics.
KW - 2D IR spectroscopy
KW - Infrared spectroscopy
KW - Optical density
KW - Pulse shaping
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U2 - 10.1016/j.vibspec.2008.10.010
DO - 10.1016/j.vibspec.2008.10.010
M3 - Article
AN - SCOPUS:67349126550
VL - 50
SP - 136
EP - 142
JO - Vibrational Spectroscopy
JF - Vibrational Spectroscopy
SN - 0924-2031
IS - 1
ER -