Recent Development of Heavy Atom-Free Triplet Photosensitizers for Photodynamic Therapy
Source abstract
Abstract
Photodynamic therapy (PDT) is an attractive method for cancer treatment. Triplet photosensitizers (PSs) are critical for this method; upon photoexcitation, efficient intersystem crossing (ISC) occurs for triplet PSs, the triplet-excited state of the triplet PSs is populated, then via intermolecular triplet energy transfer, the O2, in triplet-spin multiplicity at ground state, is sensitized to the singlet-excited state, i.e., singlet oxygen (1O2) is produced. This strong reactive oxygen species (ROS) will oxidize the biomolecules in the tumor tissue. Thus, the design of novel triplet PSs as efficient PDT agents is vital. In this review article, we will introduce the recent development of the heavy atom-free triplet PSs used for PDT, including those based on spin-orbit charge transfer ISC (SOCT-ISC), twisting of the π-conjugation framework-induced ISC, radical enhanced ISC, and thionated carbonyl-induced ISC. The ISC mechanisms and molecular structure design rationales are discussed. The less studied electron spin selectivity of the ISC of the triplet PSs is also introduced. This information is helpful for the future design of new efficient triplet PSs for PDT.
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Research context
OpenAlex topics: Luminescence and Fluorescent Materials · Porphyrin and Phthalocyanine Chemistry · Nanoplatforms for cancer theranostics
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
Affiliations
State Key Laboratory of Fine Chemicals, Frontier Science Center for Smart Materials, School of Chemical Engineering, Dalian University of Technology, Dalian 116024, China
State Key Laboratory of Chemistry and Utilization of Carbon Based Energy Resources, College of Chemistry, Xinjiang University, Urumqi 830017, China
Funding
NSFC · the State Key Laboratory of Fine Chemicals, the Fundamental Research Funds for the Central Universities · the Department of Education of the Xinjiang Uyghur Autonomous Region
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Show source-provided references
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