Sample Analysis through the use of Centrifugal-Vacuum FT-IR (CV/FT-IR)

Abstract

Sample preparation is currently considered an important bottleneck in the analysis of large numbers of samples by FT-IR spectroscopy. For aqueous or alcohol solutions, because of the very strong solvent absorptions over large regions of the infrared spectrum, extraction of the analyte from solution is often necessary prior to measurement of the spectrum, thus adding to the overall measurement time. Such an extraction procedure can be avoided with the use of a circle cell, which utilizes an internal reflection element to provide a very short effective pathlength, thereby diminishing the strong solvent absorptions. However, since the absorptions of the solute are also diminished, the applicability of this method is restricted to fairly concentrated solutions.