Imparting down/up-conversion dual channels fluorescence to luminescence metal-organic frameworks by carbon...

The rapid and simple synthesis of highly efficient multi-emission luminescent metal-organic frameworks (LMOFs) with down/up-conversion fluorescence properties becomes critical in potential optical sensing. Here, we present a luminescent dual-ligand co-assisted strategy to one-pot prepare LMOFs for multiplex fluorescence sensing using carbon dots (CDs) and 2-methylimidazole (2-MIM) as dual-ligand to induce Zn²⁺ on zeolitic imidazolate framework-8 surface (CDs/MIM-Zn). The CDs/MIM-Zn exhibited efficient fluorescence-enhanced dual channels triple-emission with Stokes and anti-Stokes type excitation profiles. With the assistance of Stokes and anti-Stokes type optical property of CDs and the intrinsic porosity of MOFs structure, a rapid and sensitive dual-channel detection excited at 370 nm and 790 nm was performed to fluorescence turn off-on detect metal ions and reduced glutathione in real blood samples with the satisfactory recoveries of 98.3-106.4%. The dual channels triple-emission strategy ensured multiplex detection of more analytes in parallel.