Recent mitochondria-immobilized fluorescent probes for high-fidelity bioimaging: From design to application

As a significant organelle, mitochondria play unique and especially essential roles in a variety of cellular activities and metabolism processes. However, the discovery of mitochondria dysfunction is tightly related to many human diseases. Currently, quantities of mitochondria-targetable fluorescent sensors and theranostic agents have been exploited to monitor various biomarkers and disease treatment. Nevertheless, these electrostatic interaction-based vehicles inevitably have a tendency to diffuse away from mitochondrial matrix leading to the inaccurate detection results and unstable localization information. Thus, to enable a precise result with a high-fidelity imaging quality, mitochondria-immobilizable probes are attracting increasing attention due to their mitochondria fixable ability and activatable sensing capability without the influence during mitophagy and depolarization process. In this review, we summarily provided an insight overview into the design strategy of mitochondria-immobilizable probes that have been employed into microenvironment, bioreactive species and enzymes detection and other phototherapy applications. Additionally, we also highlighted the challenges and opportunities of mitochondria-anchored probes in the future. We expected that this review will prompt the development of novel mitochondria-fixable fluorescent probes for better unraveling the important pathological variation and processes in mitochondria as well as other organelles.