Attenuated Total Internal Reflection Microspectroscopy of Isolated Particles: An Alternative Approach to Current Methods

Abstract

An alternative approach to conduct attenuated total internal reflection infrared microspectroscopy is described with the use of cartridge-based hemispherical internal reflection elements. The study demonstrates that the devices can be employed on any infrared microscope having reflectance capabilities. A comparison shows that the method provides the same signal-to-noise ratio in comparison to transmission studies for equal sample sizes. In addition, a 4× decrease in the sampled areas inherent with the method was verified for samples 60 μm in diameter and larger. Examples are presented that demonstrate the method's capability of studying small isolated samples without the use of a contaminating mounting media. Examples are also presented that demonstrate the potential to study samples without the effects of diffraction.

Keywords

ATR microspectroscopy Infrared microspectroscopy Particulate analysis

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