The control of the emission properties of doping materials through molecular design makes organic materials potentially promising candidates for many optoelectronic applications and devices. However, organic doping systems with high quantum yields and persistent luminescence processes have rarely been reported, and their luminescence mechanisms are still not well established. Here we developed a series of purely organic heavy-atom-free doping systems. The guest molecules can dope either donor or acceptor matrixes, both leading to an enhanced fluorescence (Φ = 63−76%) and room-temperature phosphorescence (Φ = 7.6−14.5%, τ = 119−317 ms) under ambient conditions. XRD measurements and density functional calculations results indicated ultralong phosphorescence was determined by both the cocrystalline state and the energy levels between the host and guest materials. The doping materials are fairly stable to light, heat, and humidity. This work may provide unique insight for designing doping systems and expanding the scope of organic phosphorescence applications.

The endoplasmic reticulum (ER) has a central role in the fine-tuning of environmental and internal stimuli. We herein report a ratiometric fluorescent probe, α-Naph, capable of determining basal HO in the ER. The probe specifically responds to HO. The limit of detection of the probe is as low as 38 nM, making it a feasible sensor to image intracellular basal HO. In addition, utilizing its ratiometric property, we are able to measure the concentration of HO in the ER quantitatively, eliminating the error caused by the probe concentration and environment. The intracellular concentration of HO in the ER is calculated to be 0.692 μM under normal conditions and 1.26 μM under the stimulation of phorbol myristate acetate.

Imaging of hepatocellular nitric oxide (NO) in vivo is of great importance for understanding its roles in liver diseases, but such an imaging approach is still lacking. Herein, a hepatocyte-targeting fluorescent NO sensor has been fabricated. This sensor exhibits good water solubility, excellent selectivity, and high sensitivity (∼1.62 nM). The cells and in vivo imaging experiments reveal that Gal-RhB facilitates the visualization of hepatocellular NO in both HepG2 cells and zebrafish. These results demonstrate that Gal-RhB may be a promising tool for studying the function of NO in NO-associated liver diseases.

Cadmium, a highly toxic environmental pollutant, is reported to induce toxicity and apoptosis in multiple organs and cells. The present findings showed that cadmium toxicity induces cell stress and promotes apoptosis in cardiomyocytes in a metabolic manner, by either disrupting the glucose metabolism or inhibiting mitochondrial respiratory gene expressions through AKT/mTOR pathway.