Ratiometric luminescent oxygen sensing based on dual fluorescence and phosphorescence emission in a single matrix is highly desirable, yet the designed synthesis remains challenging. Silver-chalcogenolate-cluster-based metal-organic frameworks that combine the advantages of silver clusters and metal-organic frameworks have displayed unique luminescent properties. Herein, we rationally introduce −NH 2 groups on the linkers of a silver-chalcogenolatecluster-based metal-organic framework (Ag 12 bpy-NH 2) to tune the intersystem crossing, achieving a dual fluorescence-phosphorescence emission from the same linker chromophore. The blue fluorescence component has a 100-nm gap in wavelength and 8,500,000-fold difference in lifetime relative to a yellow phosphorescence component. Ag 12 bpy-NH 2 quantifies oxygen during hypoxia with the limit of detection of as low as 0.1 ppm and 0.3 s response time, which is visualized by the naked eye. Our work shows that metal clusterbased MOFs have great potential in luminescent sensing, and the longer-lived chargeseparated states could find more photofunctional applications in solar energy transformation and photocatalysis.

Active telomerase is essential for stem cells and most cancers to maintain telomeres. The enzymatic activity of telomerase is related but not equivalent to the expression of TERT, the catalytic subunit of the complex. Here we show that telomerase enzymatic activity can be robustly estimated from the expression of a 13-gene signature. We demonstrate the validity of the expression-based approach, named EXTEND, using cell lines, cancer samples, and non-neoplastic samples. When applied to over 9,000 tumors and single cells, we find a strong correlation between telomerase activity and cancer stemness. This correlation is largely driven by a small population of proliferating cancer cells that exhibits both high telomerase activity and cancer stemness. This study establishes a computational framework for quantifying telomerase enzymatic activity and provides new insights into the relationships among telomerase, cancer proliferation, and stemness.

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Luminescent metal clusters show promise for applications in imaging and sensing. However, promoting emission from metal clusters at room temperature is a challenging task owing to the lack of an efficient approach to suppress the nonradiative decay process in metal cores. We report herein that the addition of a silver atom into a metal interstice of the radarlike thiolated silver cluster [Ag 27 (S t Bu) 14 (S) 2 (CF 3 COO) 9-(DMAc) 4 ]•DMAc (NC1, DMAc = dimethylacetamide), which is non-emissive under ambient conditions, produced another silver cluster [Ag 28 (AdmS) 14 (S) 2 (CF 3 COO) 10 (H 2 O) 4 ] (NC2) that displayed bright green room-temperature photoluminescence aided by the new ligand 1-adamantanethiol (AdmSH). The 28th Ag atom, which hardly affects the geometrical and electronic structures of the Ag-S skeleton, triggered the emission of green light as a result of the rigidity of the cluster structure.