Janus-like Bx C/C Quantum Sheets with Z-Scheme Mechanism Strengthen Tumor Photothermal-Immunotherapy in NIR-II Biowindow.

Carbon dots (CDs) are one of the most popular photothermal agents (PTAs) as a noninvasive strategy for tumor treatment. However, because of the inherent dominant fluorescent emission, the CDs-based PTAs hardly achieve a single photothermal conversion, which causes low photothermal conversion efficiency and poor photothermal performance. In this regard, finding a new CDs-based material system to greatly restrain its fluorescence to enhance its photothermal conversion efficiency is highly required, however, it is still a grand challenge. Herein, a kind of Z-scheme CDs-based PTAs consisting of 2D ultrathin nonmetallic Bx C/C Janus quantum sheets (Bx C/C JQSs) is reported to greatly enhance the photothermal conversion efficiency. It is demonstrated that the heterogeneous growth of Z-scheme Bx C/C JQSs enables the NIR-driven quick injection of hot electrons from C into the conjugated Bx C, realizing a single conversion of light to heat, and resulting in a high photothermal conversion of 60.0% in NIR-II. Furthermore, these new Z-scheme Bx C/C-polyethylene glycol JQSs display outstanding biocompatibility and show effective tumor elimination outcome both in vitro and in vivo through the synergistic photothermal-immunotherapy in the NIR-II biowindow with undetectable harm to normal tissues.

Integration of cascade delivery and tumor hypoxia modulating capacities in core-releasable satellite nanovehicles to enhance tumor chemotherapy.

Drug nanovehicles owning tumor microenvironment responsive and modulating capacities are highly demanding for effective tumor chemotherapy but still lack of exploration. Here, a kind of core-releasable satellite nanovehicles was rational constructed, which is composed of polydopamine (PDA) cores as photothermal agents and the carrier for small satellite nanoparticles (NPs) and drugs, G5Au NPs as the drug-loading satellites for deep tumor drug delivery and as catalase-like agents for relieving tumor hypoxia, doxorubicin (DOX) as the model chemotherapeutic drug loaded by both PDA and G5Au NPs, and polyethylene glycol (PEG) shells to improve biosafety. The developed drug-loaded nanovehicles (denoted as PDA-G5Au-PEG@DOX) can release G5Au satellites and DOX in stimuli-responsive manners. Thorough drug delivery in solid tumor can be realized via transporting DOX to the near-by area of and remote area from blood vessels by PDA and G5Au, respectively. Monitored by photoacoustic imaging and near-infrared fluorescence imaging, these PDA-G5Au-PEG@DOX NPs could accumulate in 4T1 tumor effectively. Under this guidance, significant tumor growth suppression could be achieved by the treatment of PDA-G5Au-PEG@DOX NPs plus laser without detectable side effects during the treatment period. The developed drug-loaded core-satellite nanovehicles with tumor microenvironment responsive/modulating capacities are of great potential in precise tumor treatments.

Construction of a Polypyrrole-Based Multifunctional Nanocomposite for Dual-Modal Imaging and Enhanced Synergistic Phototherapy against Cancer Cells.

Design and construction of multifunctional theranostic nanoplatforms are still desired for cancer-effective treatment. Herein, a kind of polypyrrole (PPy)-based multifunctional nanocomposite was designed and successfully constructed for dual-model imaging and enhanced synergistic phototherapy against cancer cells. Through graphene oxide (GO) sheet coating, PPy nanoparticles (NPs) were effectively combined with polyethylene glycol chains, Au NPs, and IR820 molecules. The obtained PGPAI NPs showed promising ability for photoacoustic/computed tomography imaging. Under near-infrared light irradiation, the PPy core and IR820 molecule effectively generated heat and reactive oxygen species (ROS), respectively. Furthermore, the loaded Au NPs owning catalase-like activity produced oxygen by decomposing H2O2 (up-regulated in tumor region), enhancing the oxygen-dependent photodynamic therapy efficacy. The formed PGPAI NPs were also proved to own desirable photothermal conversion efficiency, photothermal stability, colloidal stability, cytocompatibility, and cellular internalization behaviors. Furthermore, cell assay demonstrated that PGPAI NPs displayed enhanced synergistic phototherapy efficacy against cancer cells. These developed multifunctional nanoplatforms are promising for effective cancer theranostic applications.

Enhanced Photoacoustic and Photothermal Effect of Functionalized Polypyrrole Nanoparticles for Near-Infrared Theranostic Treatment of Tumor.

Functionalized nanomaterials with near-infrared (NIR) responsive capacity are quite promising for theranostic treatment of tumors, but formation of NIR responsive nanomaterials with enhanced theranostic ability and excellent biocompatibility is still very challenging. Herein, PEGylated indocyanine green (ICG)-loaded polypyrrole nanoparticles (PPI NPs) were designed and successfully formed through selecting polydopamine as the linkage between each component, demonstrating enhanced NIR responsive theranostic ability against tumor. By combining in vitro cell study with in vivo assay, the formed PPI NPs were proven to be fantastically biocompatible while effectively internalization in HeLa cells and retention in HeLa tumor were demonstrated by in vitro flow cytometry/confocal measurement and in vivo photoacoustic imaging assay. With the guidance of photoacoustic imaging, successful photothermal ablation of tumor was achieved by treatment with PPI NPs plus laser, which was much more effective than the group treated with NPs free of ICG. The combined enhanced photoacoustic and photothermal effect is mainly ascribed to the functionalized polypyrrole nanoparticles, which could accumulate in the tumor site more effectively with a relatively longer retention time taking advantage of the nanomaterial-induced endothelial leakiness phenomenon. All these results demonstrating that this designed PPI NPs possessing enhanced NIR responsive property hold great promise for tumor NIR theranostic applications.