6‐Triphenylphosphinehexanoic Acid Conjugated Near‐Infrared Persistent Luminescence Nanoprobe for Autofluorescence‐Free Targeted Imaging of Mitochondria in Cancer Cells

Abstract Mitochondria, as the energy provider for cells, play a key role in cell physiological processes. Mitochondrion‐targeted imaging is of great significance for understanding the physiological functions and pathology involved in various diseases. Herein, we report the fabrication of 6‐triphenylphosphinehexanoic acid (TPP) conjugated near‐infrared persistent luminescence nanoparticles (PLNP) (PLNP‐TPP) for mitochondria‐targeted imaging in cancer cells. The PLNP was prepared by doping Cr(III) into gallogermanate through a hydrothermal method. The as‐prepared PLNP showed small size, monodispersity, excellent near‐infrared (NIR) luminescence and visible light renewable NIR luminescence. The grafted TPP facilitated the transportation of PLNP‐TPP across the mitochondrial membrane and enabled staining of the mitochondrial region in live cancer cells. This work provides a promising strategy for fabricating PLNP nanoprobes to realize mitochondrial‐targeting bioimaging.