A Renal-Clearable PEGylated Semiconducting Oligomer for the NIR-II Fluorescence Imaging of Tumor

Abstract

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

Iron-chelated semiconducting oligomer nanoparticles for NIR-II fluorescence imaging-guided enhanced chemodynamic/photothermal combination therapy

“…SO-COOH was synthesized according to our previous study. 27 Amino-capped methoxy PEG (mPEG-NH 2 ) and dopamine were then conjugated onto SO-COOH sequentially via the amidation reaction. mPEG-NH 2 was first reacted with SO-COOH to give PSO, and the molar ratio between SO-COOH and mPEG-NH 2 was controlled as 1 : 2 to make sure that there were excess carboxyl groups on PSO for dopamine conjugation.…”

“…This value was lower than for PSO which we reported previously. 27 The lower quantum yield could be attributed to the quenching effect of Fe 3+ and the aggregation of PSOD. DHA@FePSOD had good photostability, its NIR-II fluorescence intensity remained almost the same during 808 nm laser irradiation for 20 min, demonstrating the feasibility of long-term imaging and PTT (Fig.…”

NIR-II Fluorescence Imaging for In Vivo Quantitative Analysis

“…Fan's group have designed and synthesized a renal-clearable polyethylene glycolated semiconductor oligomer (PSO), composed of SOs serving as NIR-II fluorescent reporter moieties and four polyethylene glycol (PEG) side chains as water-soluble enhancers. 114 PSO emits NIR-II fluorescence signals with a maximum emission wavelength of 1000 nm under 808 nm laser excitation. This PSO probe is utilized for in vivo NIR-II fluorescence imaging of tumor-bearing mice.…”

Molecular engineering of a commercially available NIR-II fluorescent cyanine dye for improved tumor targeting and imaging

“…The NIR-II fluorescence quantum yield of IR806-RGD was calculated as 0.17%, which was high enough for in vivo imaging based on previous studies. 35 The NIR-II fluorescence intensity of IR806-RGD was also determined by using in vivo NIR-II fluorescence imaging system. With the increase of concentration, the intensity increased gradually.…”