Highly Controllable Nanoassemblies of Luminescent Gold Nanoparticles with Abnormal Disassembly-Induced Emission Enhancement for In Vivo Imaging Applications.

Abstract

Assembly-induced emission enhancement has been widely observed for luminophors but it causes emission decrease after disassembly. The construction of unique nanoassemblies with disassembly-induced emission enhancement (DIEE) is demanded. Herein, by taking advantages of alterable siloxane bridge crosslinking states, we report a facile strategy to fabricate water-soluble nanoassemblies of luminescent gold nanoparticles (AuNPs) with abnormal DIEE. The fabricated AuNP nanoassemblies with dominant interparticle crosslinking showed a redshifted emission at ≈1070 nm with quantum yields (QYs) of 1.8 %. After disassembly, the nanoassemblies with increased intraparticle crosslinking exhibited a unique DIEE (>6 folds, QYs, 12 %) due to the enhanced ligand-to-metal charge transition. Besides, the disassembly facilitated renal clearance of AuNPs to reduce nonspecific retention in the body, opening new possibilities for designing highly emissive renal-clearable nanostructures toward more bioapplications.