Sensing and imaging of PPi using lanthanide-based second near-infrared luminescent probes.

Inorganic pyrophosphate (PPi), as a biologically active anion, is closely related to physiological activities and several pathological changes. Here, we reported a luminescent nanoprobe for the detection and imaging of PPi based on lanthanide nanoparticles with luminescence at the second near-infrared window modified by the tannic acid and Fe complex. A light-harvesting complex was formed after the coordination of colorless tannic acid with Fe and the luminescence of the nanoparticles was quenched through the inner-filter effect.

A simple paper-based ratiometric luminescent sensor for tetracyclines using copper nanocluster-europium hybrid nanoprobes.

Tetracyclines (TCs), as one of the broad-spectrum antibiotics, are widely used to treat bacterial infections. The residues of TCs in animal-origin foods and drinking water have raised safety concerns and affected the public health. Thus, there is a high demand to develop a simple and rapid method for the detection of TCs.