There have been several advances in instrumentation that now facilitate infrared and Raman imaging. Current Focal-Plane-Array (FPA) detectors are very robust and read out quickly for infrared imaging and fast CCD array detectors are now available for Raman imaging. For example, infrared data collection from a 128×128 FPA now takes place in 3 seconds at 4 cm-1 spectral resolution yielding 16384 spectra! Faster PC’s have also greatly facilitated the processing of the resulting data, where evolving factor analysis, neural networking, and other processing methods are readily utilized.
Human bone tissue has been investigated using chemical imaging with the goal of identifying the effectiveness of drug therapy in increasing the mineral content in bone. Polarized light and fluorescence illumination provide information relating to microfracture sites and the presence of the drug after metabolism. Bone mineral content can be correlated with the carbonate bands at 1415 and 870 wavenumbers. Results will be shown indicating the detection of improved mineral content very shortly after introduction of the regimen. Infrared imaging of tablets has also been conducted, successfully demonstrating the use of imaging for monitoring product quality and uniformity.
Raman imaging has been employed for investigating applicability for evaluating tablet uniformity and multilayer packaging materials. The high spatial resolution of Raman allowed ready profiling of the active ingredient (acetaminophen) of a non-aspirin pain reliever tablet. The confocal benefits of Raman were shown to be especially useful in probing multilayered packaging materials.
Over the years, Dr. Tague has frequently collaborated with investigators outside Bruker to improve and in some cases innovate instrumentation used for spectroscopic investigations. These efforts have led to improved analytical capabilities and in some cases novel and unique steps forward in instrumentation. He has 30 peer-reviewed publications and 2 US patents. He has given many invited lectures domestically and internationally pertaining to state-of-the-art applications of infrared and Raman spectroscopy and microspectroscopy.
Recent collaborations and research efforts have been focused on adapting and improving Raman spectroscopic instrumentation for investigating and characterizing works of art as well biological and biomedical applications.
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