Tunable Organelle Imaging by Rational Design of Carbon Dots and Utilization of Uptake Pathways

Employing one-step hydrothermal treatment of o-phenylenediamine and lysine to exploit their self- and copolymerization, four kinds of CDs (ECDs, NCDs, GCDs, and LCDs) are synthesized, possessing different surface groups (CH3, C–O–C, NH2, and COOH) and lipophilicity which endow them with various uptake pathways to achieve tunable organelle imaging. Specifically, highly lipophilic ECDs with CH3 group and NCDs with C–O–C group select passive manner to target to endoplasmic reticulum and nucleus, respectively. Amphiphilic GCDs with CH3, C–O–C and NH2 groups prefer caveolin-mediated endocytosis to locate at Golgi apparatus. Highly hydrophilic LCDs with CH3, NH2 and COOH groups are involved in clathrin-mediated endocytosis to localize in lysosomes. Besides, imaging results of cell division, three-dimensional reconstruction and living zebrafish demonstrate that the obtained CDs are promising potential candidates for specific organelle-targeting imaging.