%0 Journal Article %J Angewandte Chemie %D 2020 %T J-Aggregate-Based FRET Monitoring of Drug Release from Polymer Nanoparticles with High Drug Loading %A Liu, Yun %A Yang, Guangze %A Song Jin %A Zhang, Run %A Chen, Peng %A Tengjisi %A Wang, Lianzhou %A Chen, Dong %A Weitz, DavidA. %A Zhao, Chun‐Xia %X Understanding drug‐release kinetics is critical for the development of drug‐loaded nanoparticles. We developed a J‐aggregate‐based Förster‐resonance energy‐transfer (FRET) method to investigate the release of novel high‐drug‐loading (50 wt %) nanoparticles in comparison with low‐drug‐loading (0.5 wt %) nanoparticles. Single‐dye‐loaded nanoparticles form J‐aggregates because of the high dye‐loading (50 wt %), resulting in a large red‐shift (≈110 nm) in the fluorescence spectrum. Dual‐dye‐loaded nanoparticles with high dye‐loading using FRET pairs exhibited not only FRET but also a J‐aggregate red‐shift (116 nm). Using this J‐aggregate‐based FRET method, dye‐core–polymer‐shell nanoparticles showed two release processes intracellularly: the dissolution of the dye aggregates into dye molecules and the release of the dye molecules from the polymer shell. Also, the high‐dye‐loading nanoparticles (50 wt %) exhibited a slow release kinetics in serum and relatively quick release in cells, demonstrating their great potential in drug delivery. %B Angewandte Chemie %V 59 %P 20065-20074 %G eng %U https://onlinelibrary.wiley.com/doi/abs/10.1002/anie.202008018 %N 45