Keio University School of Medicine

Suntory Global Innovation Center


Examining water via light Aquaphotomics

Monitoring of water state changes in the human body and evaluation of health conditions

Aquaphotomics* is comprehensive analysis of water using non-invasive near-infrared spectroscopy. Scanning a solution or body with near-infrared can provides us information that reveal the dynamics of water molecules.
We aim to understand the relationship between dynamics of water and health through studies in urine and skin.

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Research Overview

Water can dissolve a variety of substances. Aquaphotomics is a technique that monitors changes in hydrogen bonds between water molecules in aqueous solution.
Near infrared light has a longer wavelength that ultraviolet or visible light, and a shorter wavelength than infrared and far infrared light.

Several absorption bands of water’s O—H bond are found in the wavelength region of near-infrared light. These absorption bands are influenced by hydrogen bonds that are formed between water molecules. The characterization of hydrogen bonds can help to reveal complex networks of water molecules in solutions and human body.

When solute is introduced into water, the rearrangements of water molecules are reflected in spectral pattern. Introduction of many solutes can make the network of water molecules more complex. To clarify it, the effects of each solute are analyzed comprehensively.

In our body system, numerous substances interact intricately with each other. We intend to understand several phenomena in body through monitoring the network of water molecules as a system (water mirror approach).

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Water in Human Body 1 Analysis of urinal water

We intend to monitor changes in urine that reflect various dietary, hydration and metabolic states.

Research Background and Objectives

Urine is an abundant source of physiologically relevant information. The majority of that information is related to daily variations in diet and water intake, and reflects the individual metabolic state. We intend to diagnose the state of body metabolism, through analysis of NIR spectral patterns of urine water content.

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Water in Human Body 2 Monitoring of Skin Water Content

We intend to establish the procedure for quantitative spectroscopic measurement of water content in human skin.

Research Background and Objectives

Water content of the skin is related to aging processes, such as decrease in barrier function and elasticity. Many devices and techniques have been developed for measuring the physical properties of the skin, but none can help us understand the relationship between water content and skin condition. Near-infrared light can penetrate the epidermis and dermis of the skin, and help us collect important information about processes in the skin. Since water is the strongest absorber in the NIR region, we expect to accurately estimate transport processes of water within skin.

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Themes 研究テーマ