Gadolinium-Chelated Conjugated Polymer-Based Nanotheranostics for Photoacoustic/Magnetic Resonance/NIR-II Fluorescence Imaging-Guided Cancer Photothermal Therapy

Abstract

Our exploiting versatile multimodal theranostic agent aims to integrate the complementary superiorities of photoacoustic imaging (PAI), second near-infrared (NIR-II, 1000-1700) fluorescence and T 1 -weighted magnetic resonance imaging (MRI) with an ultimate objective of perfecting cancer diagnosis, thus improving cancer therapy efficacy. Herein, we engineered and prepared a water-soluble gadolinium-chelated conjugated polymer-based theranostic nanomedicine (PFTQ-PEG-Gd NPs) for in vivo tri-mode PA/MR/NIR-II imaging-guided tumor photothermal therapy (PTT). Methods : We firstly constructed a semiconducting polymer composed of low-bandgap donor-acceptor (D-A) which afforded the strong NIR absorption for PAI/PTT and long fluorescence emission to NIR-II region for in vivo imaging. Then, the remaining carboxyl groups of the polymeric NPs could effectively chelate with Gd 3+ ions for MRI. The in vitro characteristics of the PFTQ-PEG-Gd NPs were studied and the in vivo multimode imaging as well as anti-tumor efficacy of the NPs was evaluated using 4T1 tumor-bearing mice. Results : The obtained theranostic agent showed excellent chemical and optical stability as well as low biotoxicity. After 24 h of systemic administration using PQTF-PEG-Gd NPs, the tumor sites of living mice exhibited obvious enhancement in PA, NIR-II fluorescence and positive MR signal intensities. Better still, a conspicuous tumor growth restraint was detected under NIR light irradiation after administration of PQTF-PEG-Gd NPs, indicating the efficient photothermal potency of the nano-agent. Conclusion : we triumphantly designed and synthesized a novel and omnipotent semiconducting polymer nanoparticles-based theranostic platform for PAI, NIR-II fluorescence imaging as well as positive MRI-guided tumor PTT in living mice. We expect that such a novel organic nano-platform manifests a great promise for high spatial resolution and deep penetration cancer theranostics.

Multiplexed NIR‐II Probes for Lymph Node‐Invaded Cancer Detection and Imaging‐Guided Surgery

“…Herein we developed an innovative fluorescence contrast agent for lymphatic imaging in the optical transparency window (NIR‐IIb, >1500 nm). This imaging modality integrated the advantages of single‐photon emission computerized tomography (SPECT)/positron emission tomography (PET)/magnetic resonance imaging (MRI) and optical imaging, providing great penetration depth, high spatial resolution, and real‐time imaging speed.…”

Grafted semiconducting polymer amphiphiles for multimodal optical imaging and combination phototherapy

“…To combine MRI with optical imaging, SPA11 with PEG and carboxyl groups on the side chains was designed and synthesized. 96 Such a design endowed SPA11 with the ability of chelating Gd 3+ ions to form SPAN11 with good water solubility ( Fig. 4a).…”

RBC Membrane Camouflaged Semiconducting Polymer Nanoparticles for Near-Infrared Photoacoustic Imaging and Photothermal Therapy

“…Recently, phototheranostic nanoagents utilizing light to collect diagnostic information and achieve therapeutic effects have gained intensive attention due to their noninvasiveness, high efficiency, and convenient maneuverability in a spatial and temporal manner [3,4]. Among the numerous phototheranostic strategies, photoacoustic imaging (PAI) and photothermal therapy (PTT) can seamlessly and synergistically match each other, because the efficacies of both PAI and PTT are mainly dependent on photothermal conversion ability, considering that PAI uses photothermally converted acoustic waves to realize ultrasound signal detection [5][6][7][8]. PAI can overcome the traditional optical penetration limitations (e.g., fluorescence imaging) since it detects phonons rather than photons under light excitation, providing superior spatial resolution, high contrast, and deep tissue penetration [7,[9][10][11].…”