Dual-Modal Probe Based on Polythiophene Derivative for Pre- and Intraoperative Mapping of Lymph Nodes by SPECT/Optical Imaging.

The metastatic spread of primary tumors to regional lymph nodes (LNs) is an important prognostic indicator for cancer staging and clinical therapy. Therefore, developing lymphatic mapping probes with improved accuracy and efficiency is of vital importance. Conjugated polymers (CPs) have been established as useful optical probes for sensitive biological and chemical detection. As a member of CPs family, polythiophene derivatives have drawn increasing attraction because of their superior photostability, signal amplification ability, and flexible structures for modification. In addition, these excellent properties allow the promising in vivo application to real-time LNs mapping. Here, we first reported a radiolabeled dual-modal probe based on the polythiophene derivative (99mTc-PTP) that was used for LNs mapping with high sensitivity and specificity by preoperative single-photon emission computed tomography imaging and intraoperative optical guidance. 99mTc-PTP exhibits an excellent radio-fluorescence guidance ability and a remarkable biocompatibility and holds great potential to be a powerful probe for noninvasive LNs mapping.