Manipulation of Photofunctions of Inorganic Nanosheets Induced by Bioluminescence

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K05407
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 32020:Functional solid state chemistry-related
• Research Institution: Nagasaki University
• Principal Investigator: KAMADA KAI 長崎大学, 工学研究科, 准教授 (90315284)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: 酵素 / ナノシート / 光触媒 / 蛍光 / バイオイメージング

Outline of Final Research Achievements

A novel photocatalytic reaction system was proposed in the present study, where semiconductor nanosheets and weak bioluminescence were utilized as photocatalysts and light source, respectively. The bioluminescence originated from biochemical reactions of enzymes of proteins excites the semiconductor nanosheets, then the nanosheets can oxidize and reduce reactants. More concretely, it was demonstrated that noble metal cations were reduced to metal nanoparticles in the presence of the nanosheets exposed to bioluminescence.
In contrast, although bioimaging employing fluorescent semiconductor nanosheets was also attempted. The titanate-based fluorescent nanosheets was successfully fabricated, but the emission strength was insufficient for bioimaging.

Free Research Field

無機材料化学

Academic Significance and Societal Importance of the Research Achievements

これまでの光触媒では光源として強い光を放つ外部光源や太陽光の利用を想定していた。本研究ではこれらと比較して極めて低い強度の光源である生物発光を効率的に利用して物質変換につなげる技術を生み出した。とりわけ、この光触媒反応では、主にタンパク質や酵素が引き起こす化学反応に伴って放出する光を利用するため、これらの生体分子１つ１つを微小な光源と考えれば、反応溶液全体に光エネルギーが均等に行き渡ることで、反応効率の向上が見込まれる。また、外部からの光照射を要しないため、夜間や光の届かない空間など、時空間の制限にとらわれることなく光触媒反応を起こせるという特長を見出すことができる。