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Liquid-phase and evanescent-wave cavity ring-down spectroscopy in analytical chemistry
L van der Sneppen1, F Ariese, C Gooijer
1Laser Center, Vrije Universiteit, Amsterdam 1081 HV, The Netherlands. wimu@nat.vu.nl
Summary
Cavity Ring-Down Spectroscopy (CRDS) offers a more sensitive alternative to traditional absorbance detection in analytical chemistry. This review explores liquid-phase and evanescent-wave CRDS for enhanced molecular detection and potential biosensor development.
Area of Science:
- Analytical Chemistry
- Spectroscopy
- Physical Chemistry
Background:
- Molecular absorbance detection is a common analytical technique due to its simplicity and direct concentration interpretation.
- However, its sensitivity is limited compared to zero-background methods like fluorescence detection.
- This necessitates the exploration of more sensitive measurement principles.
Purpose of the Study:
- To review Cavity Ring-Down Spectroscopy (CRDS) as an advanced technique for analytical chemistry.
- To focus on emerging liquid-phase CRDS and evanescent-wave (EW)-CRDS modes.
- To highlight their potential applications and future development.
Main Methods:
- Discussion of Cavity Ring-Down Spectroscopy (CRDS) principles, emphasizing long measurement pathlength and insensitivity to light source fluctuations.
- Focus on two specific CRDS modes: liquid-phase CRDS and evanescent-wave (EW)-CRDS.
- Review of current and potential applications in analytical chemistry.
Main Results:
- CRDS offers enhanced sensitivity for absorbance detection, particularly in liquid chromatography.
- Liquid-phase CRDS is being applied to improve sensitivity in analytical chemistry.
- Evanescent-wave (EW)-CRDS is in early development, primarily for studying molecule-surface interactions.
Conclusions:
- CRDS presents a promising alternative to conventional absorbance detection, offering superior sensitivity.
- Liquid-phase CRDS shows potential for advancing analytical chemistry applications.
- Evanescent-wave (EW)-CRDS may lead to the development of highly specific biosensors in the future.
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