Synthesis and characterization of a novel near-infrared fluorescent probe for applications in imaging A549 cells

Objective To design and synthesize a novel near-infrared (NIR) fluorescent probe based on indocyanine Green (ICG), that can be applied in imaging living cells. Results A highly fluorescent novel NIR fluorescent probe (IR-793) was synthesized in two steps. IR-793 had better fluorescence and optical stability than ICG. In addition, no obvious cytotoxicity effect of IR-793 was observed and cell viability was above 75% at the maximum concentration (120 nM). IR-793 also exhibited good performance in imaging living A549 cells. Conclusion IR-793, a novel NIR fluorescent probe that is stable, low-cost, highly fluorescent and low cytotoxicity, has been designed and synthesized for imaging living cells.