Enrichment polymer layers for detection of volatile vapors by ATR FT-IR

Fourier Transformed Infrared Spectroscopy (FT-IR) is an effective analytical method for the identification of organic compounds be they man made or naturally produced. There is, however, a limitation to what a normal FT-IR can detect if an analyte is in vapor phase or in low concentration. To this end, we have applied enrichment polymer layer systems (EPLS) to an attenuated total reflection (ATR) crystal waveguide to enhance detection capability for the method. These EPLS are comprised of polymers with different functionality along the backbone and provide unique interaction capabilities that can attract volatile chemicals and concentrate them in the evanescence wave region. The thickness of the polymer layers is kept on 30-50nm level. The EPLS were characterized by atomic force microscopy, ellipsometry and FT-IR. The overall goal of this work is to construct a "universal" sensor platform capable of detecting a wide range of volatile organic chemicals via infrared spectroscopy.