Synchrotron Infrared Microspectroscopy Research Articles

Development and biomedical applications of fluorescence-assisted synchrotron infrared micro-spectroscopy

It has become increasingly clear that infrared micro-spectroscopy (IRMS) can be an extremely valuable analysis tool when determining the chemical composition of biological and biomedical samples. Frequently, fluorescence illumination is required for sample characterization, which previously required the use of a separate optical microscope. We report the development and use of a single microscope for both fluorescence microscopy and synchrotron IRMS. This unique combination has been used to identify changes in the composition of newly remodeled bone after the onset of osteoporosis. In addition, other ongoing biomedical applications are discussed.

Infrared microspectroscopic studies on the pitting of AA2024‐T3 induced by acetone degreasing

AbstractAcetone degreasing of aluminum alloy AA2024‐T3, as per the ASTM E1078‐97 cleaning protocol, showed that copper‐rich intermetallic particles acted as a photocatalyst in the presence of moisture to convert the acetone remaining on the surface to acetic acid. In this work, using synchrotron infrared microspectroscopy (SIRMS), we have investigated further the acetone‐induced pitting of AA2024‐T3 that was shown earlier using XPS. Using SIRMS prior to sodium chloride mist exposure shows the presence of carboxyl groups at sites where pitting is initiated, indicating that pitting is induced by acetone. The infrared linescan and mapping performed on acetone‐degreased AA2024‐T3 exposed to sodium chloride mist shows the presence of acetyl groups surrounding the pits. Based on this work, acetone is not recommended for degreasing aluminum–copper alloys. Copyright © 2001 John Wiley & Sons, Ltd.

Organic reagent interaction with hair spatially characterized by infrared microspectroscopy using synchrotron radiation

The penetration of chemical reagents through human hair after bleaching has been spatially characterized using infrared microspectroscopy (IMS) with a synchrotron source. Chemical imaging of hair cross sections before and after bleaching was achieved with high contrast, using the peptide and lipid mid-infrared vibrational bands which are characteristic of hair. The ability to make images using functional groups as a contrast mechanism can be applied to studies of other chemical groups, if present, in the structure of the hair. As an example we show how the penetration of an organic active reagent in the hair structure can be quantified with a spatial resolution of few microns. These results demonstrate that synchrotron IMS is a powerful tool for characterizing chemical interactions of hair samples with specific cosmetic materials.

Applications of Synchrotron Infrared Microspectroscopy to the Study of Inorganic-Organic Interactions at the Bacterial- Mineral Interface

ABSTRACTSynchrotron microspectroscopy has been used to study the inorganic-organic interactions in the mid-infrared region (4000#x2013;400 cm#x2212;1) as Arthrobacter oxydans attach themselves to magnetite surfaces. Relative band intensities and band intensity ratios for functional groups of organically-derived biological molecules that are inherent to the experimental system are discussed. The molecular components as they are perturbed by interactions with water, dichromate and chromate metal ions on the mineral surfaces are investigated. Mapping of the spectral markers for the inorganic-organic interactions at the biological- mineral interfaces is presented and discussed. Comparative analyses of the synchrotron infrared microspectra suggest that the bacterial-chromium interactions depend on the solubility and toxicity of the chromium compounds.