A highly selective and instantaneous nanoprobe for detection and imaging of ascorbic acid in living cells and in vivo.

The development of a specific reaction of nanomaterials and reactive species is of fundamental importance for the determination of biomolecules. Here we report a novel nanoprobe for detection and imaging of ascorbic acid (AA) in living cells and in vivo based on the specific reaction of cobalt oxyhydroxide (CoOOH) and AA. Persistent luminescence nanoparticles (PLNPs) were used as the luminescence unit, and CoOOH nanoflakes served as the quencher. When CoOOH was modified on the surface of the PLNPs, the luminescence of the PLNPs was efficiently quenched by the CoOOH. In the presence of AA, CoOOH was reduced to Co(2+) and the luminescence of PLNPs was restored. The nanoprobe showed high selectivity and an instantaneous response. The luminescence property permits detection and imaging without external excitation, which could effectively avoid background noise and scattering of light from biological matrixes produced by in situ excitation. The current strategy provides an effective platform for monitoring and imaging reactive species in living cells and in vivo.