Broadband attenuated total reflection spectroscopy in the optical waveguide regime

Abstract

A broadband, multichannel, single mode, planar waveguide based ATR spectrometer was developed. A sensitivity enhancement of three orders of magnitude compared to the conventional transmission spectroscopic technique has been experimentally achieved. Applications to protein submonolayers adsorbed on glass surfaces provided the first results on the spectral characterization of those molecular films. The increased information content and the higher sensitivity response allowed us to experimentally determine the molecular orientation of organic films over a broad spectral range. The work developed here is a research tool that allows the investigation of some fundamental problems of molecular assemblies and a platform to develop new technological devices of high sensitivity and selectivity, such as biosensors.