Total internal reflection ellipsometry: ultrahigh sensitivity for protein adsorption on metal surfaces
1Department of Physics, Biology and Chemistry, Laboratory of Applied Optics, Linköping University, Linköping, Sweden. micpo@ifm.liu.se
Optics Letters
|April 19, 2007
Summary
Total internal reflection ellipsometry (TIRE) offers high sensitivity for detecting protein adsorption on gold films. This advanced technique provides significantly larger signals than traditional ellipsometry for studying organic layers.
Area of Science:
- Biophysics
- Surface Science
- Materials Science
Background:
- Studying protein adsorption on metal surfaces is crucial for biosensor development.
- Traditional ellipsometry has limitations in detecting low-concentration adsorbed layers.
Purpose of the Study:
- To investigate the adsorption of human serum albumin and fibrinogen on thin gold films.
- To evaluate the sensitivity and capabilities of Total Internal Reflection Ellipsometry (TIRE) for protein monolayer analysis.
Main Methods:
- Utilizing Total Internal Reflection Ellipsometry (TIRE) in spectral mode.
- Employing thin gold films as substrates for protein adsorption.
- Measuring ellipsometric angles (psi and D) to quantify adsorption.
Main Results:
- TIRE demonstrated exceptionally high sensitivity for protein monolayers on gold.
- Measured signals were orders of magnitude larger compared to traditional ellipsometry.
- Surface plasmon resonance effects significantly enhance TIRE sensitivity.
Conclusions:
- TIRE is a powerful technique for precise studies of organic layers on metal surfaces.
- The method shows potential for resolving the microstructure of adsorbed layers.
- TIRE offers a significant advancement for biosensing and surface analysis applications.
