A Renal-Clearable\nPEGylated Semiconducting Oligomer\nfor the NIR-II Fluorescence Imaging of Tumor

Abstract

Second\nnear-infrared window fluorescence imaging (NIR-II\nFI) has\nattracted tremendous attention in bioimaging. Until now, most probes\nfor NIR-II FI are nanomaterials that are metabolized via hepatobiliary\nmetabolism. Such a metabolic pathway may take several months, causing\nlong-term toxicity. Herein, we design and synthesize a renal-clearable\nPEGylated semiconducting oligomer (PSO) for the NIR-II FI of tumor.\nPSO is composed of a semiconducting oligomer (SO) backbone as an NIR-II\nfluorescence reporter and four poly(ethylene glycol) (PEG) side chains\nas water-soluble enhancers. PSO can emit an NIR-II fluorescence signal\nwith the maximum emission at 1000 nm under the excitation of 808 nm\nlight. PSO shows good biocompatibility and can be partially cleared\nout of body via renal clearance. PSO can be utilized for the NIR-II\nFI of tumor as it can effectively accumulate into tumor.