Nanoscale\nMetal–Organic Frameworks for Ratiometric\nOxygen Sensing in Live Cells

Abstract

We\nreport the design of a phosphorescence/fluorescence dual-emissive\nnanoscale metal–organic framework (NMOF), R-UiO, as an intracellular\noxygen (O₂) sensor. R-UiO contains a Pt­(II)-porphyrin ligand\nas an O₂-sensitive probe and a Rhodamine-B isothiocyanate\nligand as an O₂-insensitive reference probe. It exhibits\ngood crystallinity, high stability, and excellent ratiometric luminescence\nresponse to O₂ partial pressure. <i>In vitro</i> experiments confirmed the applicability of R-UiO as an intracellular\nO₂ biosensor. This work is the first report of a NMOF-based\nintracellular oxygen sensor and should inspire the design of ratiometric\nNMOF sensors for other important analytes in biological systems.