Grating coupled optical waveguide interferometry combined with in situ spectroscopic ellipsometry to monitor surface processes in aqueous solutions

摘要

Highlights • We have integrated two surface-sensitive optical methods into a single tool. • Special flow cell was developed to perform combined investigations. • We have described the evaluation processes in brief. • The limit of detection of the combined tool was investigated in a refractometric measurement. • The capabilities of the combined tool were demonstrated in a protein adsorption measurement. Abstract Two surface-sensitive label-free optical methods, grating coupled interferometry (GCI) and spectroscopic ellipsometry (SE) was integrated into a single instrument. The new tool combines the high sensitivity of GCI with the spectroscopic capabilities of SE. This approach allows quantification with complex optical models supported by SE and accurate measurements with the evanescent field of GCI. A flow cell was developed to perform combined and simultaneous investigations on the same sensor area in liquid (or gas) environments. The capabilities of the instrument were demonstrated in simple refractometry and protein adsorption experiments.