Synthesis of luminescent near-infrared AgInS₂ nanocrystals as optical probes for in vivo applications

Near infrared quantum dots have been receiving great attention as fluorescent optical probes for in vivo imaging applications. In this contribution, we report the synthesis and surface functionalization of cadmium free ternary AgInS₂ nanocrystals emitting in the near infrared range for successful in vitro and in vivo bioimaging applications. The FDA approved triblock copolymer Pluronic F127 was used to encapsulate the nanocrystals and made them dispersible in aqueous solution. By employing a whole body small animal optical imaging setup, we were able to use the AgInS₂ nanocrystals formulation for passive targeted delivery to the tumor site. The ultra-small crystal size, near-infrared emitting luminescence, and high quantum yield make the AgInS₂ nanocrystals an attractive candidate as a biological contrast agent for cancer sensing and imaging.