It is highly desired that satisfactory photoactive agents with ideal photophysical characteristics are explored for potent cancer phototherapeutics. Herein, bifunctional nanoparticles of low‐bandgap ...donor–acceptor (D–A)‐type conjugated‐polymer nanoparticles (CP‐NPs) are developed to afford a highly efficient singlet‐to‐triplet transition and photothermal conversion for near‐infrared (NIR) light‐induced photodynamic (PDT)/photothermal (PTT) treatment. CP‐NPs display remarkable NIR absorption with the peak at 782 nm, and perfect resistance to photobleaching. Photoexcited CP‐NPs undergo singlet‐to‐triplet intersystem crossing through charge transfer in the excited D–A system and simultaneous nonradiative decay from the electron‐deficient electron acceptor isoindigo derivative under single‐wavelength NIR light irradiation, leading to distinct singlet oxygen quantum yield and high photothermal conversion efficiency. Moreover, the CP‐NPs display effective cellular uptake and cytoplasmic translocation from lysosomes, as well as effective tumor accumulation, thus promoting severe light‐triggered damage caused by favorable reactive oxygen species (ROS) generation and potent hyperthermia. Thus, CP‐NPs achieve photoactive cell damage through their photoconversion ability for synergistic PDT/PTT treatment with tumor ablation. The proof‐of‐concept design of D–A‐type conjugated‐polymer nanoparticles with ideal photophysical characteristics provides a general approach to afford potent photoactive cancer therapy.
Ultrastable donor–acceptor low‐bandgap conjugated‐polymer nanoparticles are developed to afford a highly efficient singlet‐to‐triplet transition and nonradiative decay to simultaneously generate singlet oxygen and photohyperthermia for near‐infrared photoactive tumor ablation.
Photoconversion tunability of fluorophore dye is of great interest in cancer nanomedicine such as fluorescence imaging, photodynamic therapy (PDT), and photothermal therapy (PTT). Herein, this paper ...reports wavelength‐dependent photoconversional polymeric vesicles of boron dipyrromethene (Bodipy) fluorophore for either PDT under 660 nm irradiation or PTT under 785 nm irradiation. After being assembled within polymeric vesicles at a high drug loading, Bodipy molecules aggregate in the conformations of both J‐type and H‐type, thereby causing red‐shifted absorption into near‐infrared region, ultralow radiative transition, and ideal resistance to photobleaching. Such vesicles further possess enhanced blood circulation, preferable tumor accumulation, as well as superior cell uptake as compared to free Bodipy. In particular, the vesicles mainly generate abundant intracellular singlet oxygen for PDT treatment under 660 nm irradiation, while they primarily produce a potent hyperthermia for PTT with tumor ablation through singlet oxygen‐synergized photothermal necrosis under 785 nm irradiation. This approach provides a facile and general strategy to tune photoconversion characteristics of fluorophore dyes for wavelength‐dependent photoinduced cancer therapy.
Photoconversion‐tunable Bodipy polymeric vesicles for wavelength‐dependent photoinduced cancer therapy are demonstrated, which mainly generate abundant intracellular singlet oxygen for photodynamic therapy treatment under 660 nm irradiation, while primarily producing potent hyperthermia for photothermal therapy with tumor ablation through singlet oxygen‐synergized photothermal necrosis under 785 nm irradiation.
Bifunctional self‐assembled nanoparticles with a platinated fluorophore core with ultralow radiative transition are developed, which can generate both singlet oxygen and the photothermal effect for ...synergistic photodynamic and photothermal therapy with tumor ablation.
Smart nanocarriers are of particular interest as nanoscale vehicles of imaging and therapeutic agents in the field of theranostics. Herein, we report dually pH/reduction-responsive terpolymeric ...vesicles with monodispersive size distribution, which are constructed by assembling acetal- and disulfide-functionalized star terpolymer with near-infrared cyanine dye and anticancer drug. The vesicular nanostructure exhibits multiple theranostic features including on-demand drug releases responding to pH/reduction stimuli, enhanced photothermal conversion efficiency of cyanine dye, and efficient drug translocation from lysosomes to cytoplasma, as well as preferable cellular uptakes and biodistribution. These multiple theranostic features result in ultrahigh-contrast fluorescence imaging and thermo-chemotherapy-synergized tumor ablation. The dually stimuli-responsive vesicles represent a versatile theranostic approach for enhanced cancer imaging and therapy.
Photothermal therapy (PTT) is of particular importance as a highly potent therapeutic modality in cancer therapy. However, a critical challenge still remains in the exploration of highly effective ...strategy to maximize the PTT efficiency due to tumor thermoresistance and thus frequent tumor recurrence. Here, a rational fabrication of the micelles that can achieve mutual synergy of PTT and molecularly targeted therapy (MTT) for tumor ablation is reported. The micelles generate both distinct photothermal effect from Cypate through enhanced photothermal conversion efficiency and pH‐dependent drug release. The micelles further exhibit effective cytoplasmic translocation of 17‐allylamino‐17‐demethoxygeldanamycin (17AAG) through reactive oxygen species mediated lysosomal disruption caused by Cypate under irradiation. Translocated 17AAG specifically bind with heat shock protein 90 (HSP90), thereby inhibiting antiapoptotic p‐ERK1/2 proteins for producing preferable MTT efficiency through early apoptosis. Meanwhile, translocated 17AAG molecules further block stressfully overexpressed HSP90 under irradiation and thus inhibit the overexpression of p‐Akt for achieving the reduced thermoresistance of tumor cells, thus promoting the PTT efficiency through boosting both early and late apoptosis of Cypate. Moreover, the micelles possess enhanced resistance to photobleaching, preferable cellular uptake, and effective tumor accumulation, thus facilitating mutually synergistic PTT/MTT treatments with tumor ablation. These findings represent a general approach for potent cancer therapy.
This study reports a rational fabrication of the micelles that can achieve mutual synergy of photothernal therapy (PTT) and molecularly targeted therapy (MTT) for effective tumor ablation through enhanced PTT by blocking stressfully overexpressed HSP90 under irradiation using 17‐allylamino‐17‐demethoxygeldanamycin (17AAG) and preferable MTT efficiency by reactive oxygen species mediated effective cytoplasmic translocation of 17AAG caused by Cypate under irradiation.
The development of molecular frameworks derived from binuclear platinum(II) aromatic Schiff base (salphen) complexes and their supramolecular chemistry have been undertaken. A series of axially ...rotating (Pt‐salphen)2 luminophores, tethered in a cofacial manner by a rigid linker (xanthene, 1; dibenzofuran, 2; biphenylene, 3), was synthesized in which the O(salphen) groups are potentially amenable for guest‐binding. The molecular structures of 1 and 3 have been determined by X‐ray crystallography, revealing intra‐ and intermolecular π‐stacking interactions, as well as contrasting syn (1) and anti (3) configurations, for the (Pt‐salphen)2 moiety. All complexes are luminescent in solution at room temperature. Their photophysical and solvatochromic properties have been examined, and the emissions are assigned to mixed triplet O(p)/Pt(d)→π*(diimine) excited states. The red‐shifted fluid emissions and lower quantum yields of 1 and 3, relative to 2, are ascribed to enhanced intramolecular π‐stacking interactions. Photophysical changes and selective responses to metal ions (particularly Pb2+) have been investigated by using various spectroscopic methods and DFT calculations, and through comparative studies with control complexes. A plausible binding mechanism is proposed based on occupation of the O(salphen)‐binding cavity, which induces perturbation of intramolecular π–π interactions, and hence the self‐quenching and emission properties, of the (Pt‐salphen)2 unit.
To π or not to π? The ratiometric phosphorescent ion‐selective responses of axially rotating binuclear assemblies have been investigated by using X‐ray crystallography, DFT calculations, and various spectroscopic techniques to provide an insight into the binding mechanism (see figure). These results may carry important implications for stimuli‐responsive luminescent host complexes that engage in intramolecular interactions.
Bismuth silicate (Bi4Si3O12, BSO) thin films have been fabricated by sol–gel process. The stable sol was synthesized by using Bi(NO3)3·5H2O and Si(OC2H5)4 (TEOS) as the precursors, acetic acid and ...2-ethoxyethanol as the solvents. The thin film precursor was deposited onto SiO2 substrates by spin-coating at 3000rpm and was dried at 110°C. X-ray diffraction showed that BSO phase starts to form at 700°C and single-phase BSO polycrystalline thin films were obtained at 800°C. The micromorphology and luminescent properties of coated films were characterized by means of scanning electron microscopy and fluorophotometer respectively.
A new class of shape-persistent coordination motifs bearing integrated design features that allow reporting of molecular-level perturbations, and their colorimetric and luminescent responses to metal ...ions, are described.
A critical issue in photodynamic therapy (PDT) is inadequate reactive oxygen species (ROS) generation in tumors, causing inevitable survival of tumor cells that usually results in tumor recurrence ...and metastasis. Existing photosensitizers frequently suffer from relatively low light‐to‐ROS conversion efficiency with far‐red/near‐infrared (NIR) light excitation due to low‐lying excited states that lead to rapid non‐radiative decays. Here, a neutral Ir(III) complex bearing distyryl boron dipyrromethene (BODIPY‐Ir) is reported to efficiently produce both ROS and hyperthermia upon far‐red light activation for potentiating in vivo tumor suppression through micellization of BODIPY‐Ir to form “Micelle‐Ir”. BODIPY‐Ir absorbs strongly at 550–750 nm with a band maximum at 685 nm, and possesses a long‐lived triplet excited state with sufficient non‐radiative decays. Upon micellization, BODIPY‐Ir forms J‐type aggregates within Micelle‐Ir, which boosts both singlet oxygen generation and the photothermal effect through the high molar extinction coefficient and amplification of light‐to‐ROS/heat conversion, causing severe cell apoptosis. Bifunctional Micelle‐Ir that accumulates in tumors completely destroys orthotopic 4T1 breast tumors via synergistic PDT/photothermal therapy (PTT) damage under light irradiation, and enables remarkable suppression of metastatic nodules in the lungs, together without significant dark cytotoxicity. The present study offers an emerging approach to develop far‐red/NIR photosensitizers toward potent cancer therapy.
A far‐red/near‐infrared (NIR)‐absorbing neutral Ir(III) complex (BODIPY‐Ir) bearing the distyryl boron dipyrromethene motif and its encapsulated micelles (Micelle‐Ir) are reported for potent photodynamic/photothermal therapy (PDT/PTT) against aggressive tumors. Micelle‐Ir demonstrates a remarkable therapeutic efficacy against primary breast and metastatic lung tumors through bifunctional PDT/PTT damage in a cooperative manner.
High‐performance photosensitizers are highly desired for achieving selective tumor photoablation in the field of precise cancer therapy. However, photosensitizers frequently suffer from limited tumor ...suppression or unavoidable tumor regrowth due to the presence of residual tumor cells surviving in phototherapy. A major challenge still remains in exploring an efficient approach to promote dramatic photoconversions of photosensitizers for maximizing the anticancer efficiency. Here, a rational design of boron dipyrromethene (BDP)‐based conjugated photosensitizers (CPs) that can induce dually cooperative phototherapy upon light exposure is demonstrated. The conjugated coupling of BDP monomers into dimeric BDP (di‐BDP) or trimeric BDP (tri‐BDP) induces photoconversions from fluorescence to singlet‐to‐triplet or nonradiative transitions, together with distinctly redshifted absorption into the near‐infrared region. In particular, tri‐BDP within nanoparticles shows preferable conversions into both primary thermal effect and minor singlet oxygen upon near‐infrared light exposure, dramatically achieving tumor photoablation without any regrowth through their cooperative anticancer efficiency caused by their dominant late apoptosis and moderate early apoptosis. This rational design of CPs can serve as a valuable paradigm for cooperative cancer phototherapy in precision medicine.
The rational design of boron‐dipyrromethene‐based conjugated photosensitizers within nanoparticles is reported. These systems can induce dually cooperative phototherapy through controllable photoconversions for achieving tumor photoablation surgery upon NIR light exposure.
