Rare earth-modified yellow carbon dots for long-term imaging in cells and zebrafish

Carbon dot (CDs) materials are typically hindered by aggregation-caused quenching (ACQ) effect. However, there are limitations in terms of their development and application. The introduction of aggregation-induced emission (AIE) characteristics into CDs has emerged as a viable solution to this challenge. In this work, we synthesized a novel yellow fluorescence (FL) rare earth-doped AIE CDs (named Y-CDs), which integrate the benefits of AIE materials, rare earth materials, and CDs. Y-CDs exhibit bright yellow FL, good temperature sensitivity and pH response properties. In cell imaging, Y-CDs showed excellent targeting capability towards the nuclear in HeLa cells. Y-CDs also showed excellent biocompatibility and safety in imaging of zebrafish embryos and zebrafish. Even on the 10th day following culture of zebrafish embryos, the digestive system and lens of zebrafish can be accurately located and imaged. The work presented here suggests the great potential of replacing commercial dyes with Y-CDs for highly specific nuclear labeling and bioimaging.