Bright near-infrared aggregation-induced emission dots for long-term bioimaging in vitro/vivo

Abstract

Advanced hepatocarcinoma is almost incurable and has caused a huge number of deaths every year. Noninvasive long-term cell tracing is an efficient and important tool to understand genesis, development and evolution of cancer cells. Bright organic luminescent dots (named TNZ2tPPI-Tat NPs) with unique aggregation-induced near-infrared red emission (NIR-AIE), prepared in this contribution, enjoy the advantages of desirable biocompatibility, great water dispersibility, high photoluminescent quantum efficiency (32 %), large Stokes shift (166 nm), anti-background interference and great photostability. Moreover, the thus-obtained AIE-active NPs show ultralong fluorescent bioimaging (7 days) in MHCC97-H cells, and still keep clear fluorescent signals after 5 generations in three hepatic cells (Lo2, MHCC97-H, Hep 3B). In vivo fluorescent imaging demonstrates that TNZ2tPPI-Tat NPs still maintain strong brightness over 26 days, suggest great stability of such bright NPs. Further compare with the counterparts of commercial fluorescent probes such as Cy5 and AF647, such AIE dots enjoy more superior performances in the aspect of fluorescent intensity and long-term bioimaging efficiency, which is promising candidate to serve as noninvasive long-term cell tracker.