Amino-terminated carbon dots for imaging Golgi apparatus polarity in live cells

Cellular polarity plays a crucial role in numerous pathological and biological processes. For example, the polarity of the Golgi apparatus strongly influences the intracellular protein processing and transport. The development of fluorescent probes for tracking of subcellular levels of polarity changes remains a great challenge. Herein, amino-terminated carbon dots (CDs) which have superior Golgi apparatus targeting ability and polarity-sensitive property were designed and fabricated by the mixing of p-phenylenediamine and ethylenediamine through a simple solvothermal route. CDs allowed effectively imaging of Golgi apparatus morphological dynamics during cell division and cell death, while folic acid-conjugated CDs possessed high folate-receptor binding affinity and could be used to identify cancer cells. Importantly, the Golgi polarity in apoptotic cells was found to be higher than that of non-apoptotic cells. This work provided a reliable and robust way to real-time track the changes of Golgi apparatus and the local polarity variation, implying the great potential of CDs for the apoptosis evaluation and therapeutic drug screening.