Visualization of Reaction-diffusion Phenomena of Aqueous Solutions in Microfluidic Channels Using Near-infrared Absorption Imaging Technique

Abstract

This paper summarizes a principle and an imaging device for near-infrared (NIR) absorption imaging method developed for microfluidic chips. The NIR absorption imaging method provides temperature and concentration images using the correlation between temperature or solute concentration and the vibration mode of water molecule. By performing image calculation using wavelengths which are sensitive to temperature and concentration, temperature and concentration imaging is enabled. In the experiments, temperature and concentration imaging during reaction and diffusion of aqueous solution in microchannel is demonstrated. Also, the phenomenon analysis is shown based on the imaging results.