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Title: A New Sample Substrate for Imaging and Correlating Organic and Trace Metal Composition in Biological Cells and Tissues

Abstract

Many disease processes involve alterations in the chemical makeup of tissue. Synchrotron-based infrared (IR) and X-ray fluorescence (XRF) microscopes are becoming increasingly popular tools for imaging the organic and trace metal compositions of biological materials, respectively, without the need for extrinsic labels or stains. Fourier transform infrared microspectroscopy (FTIRM) provides chemical information on the organic components of a material at a diffraction-limited spatial resolution of 2-10 {mu}m in the mid-infrared region. The synchrotron X-ray fluorescence (SXRF) microprobe is a complementary technique used to probe trace element content in the same systems with a similar spatial resolution. However to be most beneficial, it is important to combine the results from both imaging techniques on a single sample, which requires precise overlap of the IR and X-ray images. In this work, we have developed a sample substrate containing a gold grid pattern on its surface, which can be imaged with both the IR and X-ray microscopes. The substrate consists of a low trace element glass slide that has a gold grid patterned on its surface, where the major and minor parts of the grid contain 25 and 12 nm gold, respectively. This grid pattern can be imaged with the IR microscope becausemore » the reflectivity of gold differs as a function of thickness. The pattern can also be imaged with the SXRF microprobe because the Au fluorescence intensity changes with gold thickness. The tissue sample is placed on top of the patterned substrate. The grid pattern's IR reflectivity image and the gold SXRF image are used as fiducial markers for spatially overlapping the IR and SXRF images from the tissue. Results show that IR and X-ray images can be correlated precisely, with a spatial resolution of less than one pixel (i.e., 2-3 microns). The development of this new tool will be presented along with applications to paraffin-embedded metalloprotein crystals, Alzheimer's disease, and hair composition.« less

Authors:
; ; ; ; ;
Publication Date:
Research Org.:
Brookhaven National Laboratory (BNL) National Synchrotron Light Source
Sponsoring Org.:
Doe - Office Of Science
OSTI Identifier:
929862
Report Number(s):
BNL-80429-2008-JA
Journal ID: ISSN 1618-2642; TRN: US0806662
DOE Contract Number:
DE-AC02-98CH10886
Resource Type:
Journal Article
Resource Relation:
Journal Name: Analytical and Bioanalytical Chemistry; Journal Volume: 387; Journal Issue: 5
Country of Publication:
United States
Language:
English
Subject:
43 PARTICLE ACCELERATORS; ANIMAL CELLS; ANIMAL TISSUES; BIOLOGICAL MATERIALS; CRYSTALS; DISEASES; ELEMENTS; FLUORESCENCE; GOLD; GRIDS; HAIR; METALLOPROTEINS; METALS; MICROSCOPES; REFLECTIVITY; SPATIAL RESOLUTION; SUBSTRATES; SYNCHROTRON RADIATION; TRACE AMOUNTS; TRIOCTYLPHOSPHINE SULFIDE; X-RAY FLUORESCENCE ANALYSIS; national synchrotron light source

Citation Formats

Miller,L., Wang, Q., Smith, R., Zhong, H., Elliott, D., and Warren, J. A New Sample Substrate for Imaging and Correlating Organic and Trace Metal Composition in Biological Cells and Tissues. United States: N. p., 2007. Web. doi:10.1007/s00216-006-0879-2.
Miller,L., Wang, Q., Smith, R., Zhong, H., Elliott, D., & Warren, J. A New Sample Substrate for Imaging and Correlating Organic and Trace Metal Composition in Biological Cells and Tissues. United States. doi:10.1007/s00216-006-0879-2.
Miller,L., Wang, Q., Smith, R., Zhong, H., Elliott, D., and Warren, J. Mon . "A New Sample Substrate for Imaging and Correlating Organic and Trace Metal Composition in Biological Cells and Tissues". United States. doi:10.1007/s00216-006-0879-2.
@article{osti_929862,
title = {A New Sample Substrate for Imaging and Correlating Organic and Trace Metal Composition in Biological Cells and Tissues},
author = {Miller,L. and Wang, Q. and Smith, R. and Zhong, H. and Elliott, D. and Warren, J.},
abstractNote = {Many disease processes involve alterations in the chemical makeup of tissue. Synchrotron-based infrared (IR) and X-ray fluorescence (XRF) microscopes are becoming increasingly popular tools for imaging the organic and trace metal compositions of biological materials, respectively, without the need for extrinsic labels or stains. Fourier transform infrared microspectroscopy (FTIRM) provides chemical information on the organic components of a material at a diffraction-limited spatial resolution of 2-10 {mu}m in the mid-infrared region. The synchrotron X-ray fluorescence (SXRF) microprobe is a complementary technique used to probe trace element content in the same systems with a similar spatial resolution. However to be most beneficial, it is important to combine the results from both imaging techniques on a single sample, which requires precise overlap of the IR and X-ray images. In this work, we have developed a sample substrate containing a gold grid pattern on its surface, which can be imaged with both the IR and X-ray microscopes. The substrate consists of a low trace element glass slide that has a gold grid patterned on its surface, where the major and minor parts of the grid contain 25 and 12 nm gold, respectively. This grid pattern can be imaged with the IR microscope because the reflectivity of gold differs as a function of thickness. The pattern can also be imaged with the SXRF microprobe because the Au fluorescence intensity changes with gold thickness. The tissue sample is placed on top of the patterned substrate. The grid pattern's IR reflectivity image and the gold SXRF image are used as fiducial markers for spatially overlapping the IR and SXRF images from the tissue. Results show that IR and X-ray images can be correlated precisely, with a spatial resolution of less than one pixel (i.e., 2-3 microns). The development of this new tool will be presented along with applications to paraffin-embedded metalloprotein crystals, Alzheimer's disease, and hair composition.},
doi = {10.1007/s00216-006-0879-2},
journal = {Analytical and Bioanalytical Chemistry},
number = 5,
volume = 387,
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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