title: Indocyanine green-loaded hollow mesoporous silica nanoparticles as an activatable theranostic agent.
abstract: Here we report indocyanine green (ICG)-loaded hollow mesoporous silica nanoparticles (ICG@HMSNP) as an activatable theranostic platform. Near-infrared fluorescence and singlet oxygen generation of ICG@HMSNP was effectively quenched (i.e. turned off) in its native state because of the fluorescence resonance energy transfer between ICG molecules. Therefore, ICG@HMSNP was nonfluorescent and nonphototoxic in the extracellular region. After the nanoparticles entered the cancer cells via endocytosis, they became highly fluorescent and phototoxic. In addition, intracellular uptake of ICG@HMSNP was 2.75 times higher than that of free ICG, resulting in an enhanced phototherapy of cancer.
authors.affiliation: Molecular Imaging & Therapy Branch, National Cancer Center, 323 Ilsan-ro, Ilsandong-gu, Goyang-si, Gyeonggi-do 10408, Republic of Korea.
authors.forename: Suk Ho
authors.initials: SH
authors.lastname: Hong
authors.forename: Hyunjin
authors.initials: H
authors.lastname: Kim
authors.forename: Yongdoo
authors.initials: Y
authors.lastname: Choi