Enhanced FTIR Spectroscopy of Biological Liquid Samples Confined Between Ge Hemispherical ATR Element and Al Coated Glass Substrate

Abstract

We demonstrated a modified SEIRA approach, which can be easily utilized for measurements of various liquid samples, including biological specimens. In addition, the possibility of using Al, known as non-typical SERS metal, for enhancement of IR signal was demonstrated with enhancement factor varied from 10 to 1000 for different IR bands. This method is easily accessible and does not require deposition of metal on expensive internal reflection element. Instead metal can be deposited on cheap glass substrate, which is used in the suggested set up as top window during SEIRA measurements. Finally, the thickness of the analyte can be controlled by the position of the pres-sure applicator when using a grazing angle ATR attachment.