Development of Deep Cellular Cancer Therapy Using Photosensitizer-Encapsulated Upconversion Particles

2022 Fiscal Year Final Research Report

• Project/Area Number: 19K12813
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 90120:Biomaterials-related
• Research Institution: Yonago National College of Technology
• Principal Investigator: URUMA YOSHIYUKI 米子工業高等専門学校, その他部局等, 教授 (70442457)
• Co-Investigator(Kenkyū-buntansha): 小沼 邦重 京都大学, 医学研究科, 特定助教 (90597890)
• Project Period (FY): 2019-04-01 – 2023-03-31
• Keywords: 光増感剤 / 一重項活性酸素 / 低酸素 / 光線力学

Outline of Final Research Achievements

The photosensitizer-containing upconversion nanoparticles were made of Y (yttrium), which forms the nucleus of the particles, and Yb (ytterbium) and Tm (thulium), which cause upconversion. 8-methoxypsoralene and phthalocyanines were used as photosensitizers.
The NaYF4 nucleus nanoparticles were prepared by an existing method, and then the particles were treated with ethanol and 2MHCl solution, and the excess acid was washed out with ethanol. The surface of the particles was coated with silica to enhance their water solubility and biocompatibility, and TEM measured the results. Cell-based experiments were conducted using the obtained particles. The particles showed significant cytotoxicity in HeLa cells and DLD-1 cells.

Free Research Field

有機合成化学

Academic Significance and Societal Importance of the Research Achievements

日本人の２人に１人は将来がんになると推測され、その内３人に１人は死亡すると言われる。本申請研究では、次世代のがん治療法として注目を集める光線力学療法の治療上の課題を解決し細胞深部でも適応できる技術にすることを目的とする。課題克服に向け鍵となるのは近赤外光線を可視光線に変換するアップコンバージョン技術とがん細胞である。我々は、ワールブルク効果に基づいた光増感剤の合成に成功しており、本申請研究ではＵＣＮ内部に、我々が開発した特異的にがん細胞への集積能をもつ光増感剤を内包させ、UCN表面には親水性、機能性を付与した細胞内動態特性を有する新規機能素子を調整した。