Emerging Design Principle of Near-Infrared Upconversion Sensitizer Based on Mitochondria-Targeted Organic Dye for Enhanced Photodynamic Therapy

Chemistry. 2021 Oct 14. doi: 10.1002/chem.202102866. Online ahead of print.ABSTRACTUpconversion luminescent (UCL) triggered photodynamic therapy (PDT) affords superior outcome for cancer treatment. However, conventional UCL materials which all work as multiphoton absorption (MPA) process, inevitably need extremely high power density far over the maximum permissible exposure (MPE) to laser. Here, an one-photon absorption molecular upconversion sensitizer Cy5.5-Br based on frequency upconversion luminescent (FUCL) is designed for PDT. The unusual super heavy atom effect (SHAE) in Cy5.5-Br strongly enhance its spin-orbit coupling (0.23 cm-1), triplet quantum yield (11.1%) and triplet state lifetime (18.8 μs) while the potential hot-band absoption of Cy5.5-Br are well maintained. Importantly, Cy5.5-Br can efficiently target to the tumour site and kill cancer cells by destroying mitochondria under a biosafety MPE to 808 nm laser. The photostability and antitumor results are obviously superior to that of Stoke process. This work first provide a design criterion for FUCL dyes to realize effective PDT upon a biosafety optical density, possibly being more clinical benefits than conventional MPA materials.PMID:34648222 | DOI:10.1002/chem.202102866
Source: Chemistry - Category: Chemistry Authors: Source Type: research