Establishment of in vivo measurement of glucose anomers using near-infrared spectroscopy

2018 Fiscal Year Final Research Report

• Project/Area Number: 17K15356
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Agricultural environmental engineering/Agricultural information engineering
• Research Institution: Keio University
• Principal Investigator: Tanaka Sae 慶應義塾大学, 医学部(信濃町), 助教 (60770336)
• Project Period (FY): 2017-04-01 – 2019-03-31
• Keywords: 近赤外光 / グルコース / 異性体 / 糖類 / 多変量解析

Outline of Final Research Achievements

Glucose, which is used as energy source, exists in an aqueous solution in a state in which two isomers are mixed in a ratio of 4: 6. This ratio may change depending on the temperature, the presence of ions, and the enzyme reaction, but there has been no method for detecting the change in isomer ratio in the living body or the reaction solution in situ. In this study, near infrared spectroscopy that has a high bio-permeability was used to analyze the near-infrared spectra of glucose isomer in an aqueous solution and quantify the isomer ratio. As a result, the two isomers of glucose showed differences in spectra at multiple wavelength regions, including 1,742 nm, which is the highest correlation with the isomer ratio in PLS regression analysis. In addition, it was shown that quantification of the isomer ratio using spectra around 1,742 nm is effective even under the influence of temperature change and ions.

Free Research Field

分光学

Academic Significance and Societal Importance of the Research Achievements

これまでの近赤外光を用いた研究では、二つの異性体の存在を無視して、グルコースを一つの化学物質として扱っていた。しかしながら、近赤外光は分子の構造に依存して波形が変わることから、各異性体は異なる波形を示す可能性があった。本研究はその可能性に着目して解析を行うことで、これまでの研究が見逃していた異性体間の波形変化を明らかにした。この成果は、波形中に現れる分子の正確な情報を提供することで、血糖値の非侵襲測定をはじめとする糖の測定システム構築の発展を促すことが期待される。さらに、本研究の成果から、異性体割合の検出系を構築することで、がん細胞などの糖代謝の異なる細胞を検出できる可能性も考えられる。