Red/NIR emission carbonized polymer dots based on citric acid-benzoylurea and their application in lymph nodes imaging

Identification of lymph nodes (LNs) is critical for studies of the structure, the role in disease development, and the efficacy of disease treatment. Carbonized polymer dots (CPDs) are expected to be potential LNs-targeted imaging agents due to their excellent properties with special structure, better photoluminescence (PL) and great biocompatibility. Herein, a red/near infrared (NIR) emission CPDs (RCPDs) with one and two-photon bioimaging based on citric acid (CA) and benzoylurea (BU) are prepared. Notably, the RCPDs are capable of targeting LNs for imaging. Lymphocyte homing has been demonstrated to be the cellular mechanism of RCPDs target LNs imaging. This work has developed a new nanomaterial for targeted imaging of LNs, while the biological applications of CPDs have been expanded and deepened.