Research

Since the early 90's the MML has been exploring the capabilities and limitations of both infrared and Raman microspectroscopy. Major efforts have been focused on understanding the quantitative aspects of the techniques and pushing the limits in terms of spatial and volumetric resolution. In 1991 we undertook a comprehensive study which investigated the spatial resolution of a commercial infrared microscope (IRPLAN). The study demonstrated that the spatial resolution was significantly degraded by over aperturing and was improved by the use of redundant apertures (spatial resolution).

After that study we investigated ways in which to improve the spatial resolution by using attenuated total internal reflection (ATR) microspectroscopy. The method is essentially an immersion method which improves the x-y spatial resolution.Added benefits of the method include an improved volumetric resolution and minimal sample preparation. Beginning in 1999 and later collaborating with Procter and Gamble in 2001 we developed ATR FTIR imaging. This new method significantly improved the spatial resolution of the method. However, one drawback to the method was the cost of the instrumentation. Based on our earlier research in ATR mapping and working in conjunction with Perkin Elmer a more economical solution was developed. In 2006 Perkin Elmer introduced An ATR imaging accessory for use on their Spotlight 300 and 400 infrared imaging microscopes.

Since 2006 we have been using the method to study kidney disease in collaboration with Dr. Andrew Evan of the International Kidney Stone Institute in Indianapolis. We have also used the method to detect counterfeit pharmaceuticals in collaboration with Dr. Adam Lanzarotta at the Food and Drug Administrations Forensic Chemistry Center in Cincinnati.

More details concerning our research in infrared microspectroscopy, Raman microspectroscopy, instrument development, methods development and optical design can be found on Research Highlights and Publication pages.