Improvement of Photodynamic Activity by a Stable System Consisting of a C60 Derivative and Photoantenna in Liposomes

Risako Shimada; Shodai Hino; Keita Yamana; Riku Kawasaki; Toshifumi Konishi; Atsushi Ikeda

doi:10.1021/acsmedchemlett.1c00691

Improvement of Photodynamic Activity by a Stable System Consisting of a C₆₀ Derivative and Photoantenna in Liposomes

ACS Med Chem Lett. 2022 Mar 1;13(4):641-647. doi: 10.1021/acsmedchemlett.1c00691. eCollection 2022 Apr 14.

Authors

Risako Shimada¹, Shodai Hino², Keita Yamana¹, Riku Kawasaki¹, Toshifumi Konishi³, Atsushi Ikeda¹

Affiliations

¹ Applied Chemistry Program, Graduate School of Advanced Science and Engineering, Hiroshima University, 1-4-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8527, Japan.
² Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), 1-8-31 Midorigaoka, Ikeda, Osaka 563-8577, Japan.
³ Department of Materials Science and Engineering, Shibaura Institute of Technology, 307 Fukasaku, Minuma-ku, Saitama 337-8570, Japan.

Abstract

A dyad system comprising a lipid membrane-incorporated fullerene derivative with an N,N-dimethylpyrrodinium group (C₆₀-1) and a photoantenna molecule (DiD) did not exhibit the high photodynamic activity expected based on its singlet oxygen generation ability. Comparison with a fullerene derivative with an amide substituent (C₆₀-2) suggested the cause to be that some of the fullerene derivative had been released from the liposomes, partly disrupting the dyad system. The dyad system of C₆₀-2 and DiD exhibited about twice the photodynamic activity toward HeLa cells as that of C₆₀-1 and DiD, due to the suppression of the release of the fullerene derivative from the liposomes. The hydrophobicity/hydrophilicity balance of the substituent in fullerene derivatives was shown to be very important to obtain a dyad system in liposomes characterized by high photodynamic activity.