Noninvasive control over the reversible generation of singlet oxygen ( 1 O 2 ) has found the practical significance in benefiting photodynamic therapy. In this study, we developed a new dual-stage metallacycle (M) by using a photosensitizer and photochromic switch as the functional building blocks, which enables the noninvasive "off− on" switching of 1 O 2 generation through the efficient intramolecular energy transfer. Due to the proximal placement of the functional entities within the well-defined metallacyclic scaffold, 1 O 2 generation in the ring-closed form state of the photochromic switch (C-M) is quenched by photoinduced energy transfer, whereas the generation of 1 O 2 in the ring-open form state (O-M) is activated upon light irradiation. More interestingly, the metallacycle-loaded nanoparticles with relatively high stability and water solubility were prepared, which allow for the delivery of metallacycles to cancer cells via endocytosis. Their theranostic potential has been systematically investigated both in vitro and in vivo. Under the light irradiation, the designed ring-open form nanoparticles (O-NPs) show remarkable higher cytotoxicity against cancer cells compared to the ring-closed form nanoparticles (C-NPs). In vivo experiments also revealed that tumors can be very efficiently eliminated by the designed nanoparticles under light irradiation with the ability to regulate in vivo generation of singlet oxygen. All these results demonstrated that the supramolecular coordination complexes with a dual-stage state provide a highly efficient nanoplatform for noninvasive control over the reversible generation of 1 O 2 , thus allowing for their promising applications in tumor treatment and beyond.
The
construction of supramolecular coordination complexes (SCCs)
featuring prominent cancer theranostic functions is an appealing yet
significantly challenging task. In this study, we rationally designed
and facilely constructed a prism-like metallacage C-DTTP with efficient
fluorescence emission in the second near-infrared (NIR-II) region
through the assembly of an aggregation-induced emission-active four-arm
ligand with 90° Pt acceptors Pt(PEt3)2(OTf)2. C-DTTP held the longest maximum emission wavelength (1005
nm) compared with those previously reported SCCs up to now and exhibited
both a high photothermal conversion efficiency (39.3%) and significantly
superior reactive oxygen species generation behavior to the precursor
ligand. In vitro and in vivo assessments demonstrated that the metallacage-loaded
nanoparticles with excellent biocompatibility and stability were capable
of simultaneously affording precise tumor diagnosis and complete tumor
elimination by means of NIR-II fluorescence/photothermal dual imaging-guided
photodynamic/photothermal synergistic therapy.
Transition metal sulfides hold promising potentials as Li‐free conversion‐type cathode materials for high energy density lithium metal batteries. However, the practical deployment of these materials is hampered by their poor rate capability and short cycling life. In this work, the authors take the advantage of hollow structure of CuS nanoboxes to accommodate the volume expansion and facilitate the ion diffusion during discharge–charge processes. As a result, the hollow CuS nanoboxes achieve excellent rate performance (≈371 mAh g−1 at 20 C) and ultra‐long cycle life (>1000 cycles). The structure and valence evolution of the CuS nanobox cathode are identified by scanning electron microscopy, transmission electron microscopy, and X‐ray photoelectron spectroscopy. Furthermore, the lithium storage mechanism is revealed by galvanostatic intermittent titration technique and operando Raman spectroscopy for the initial charge–discharge process and the following reversible processes. These results suggest that the hollow CuS nanobox material is a promising candidate as a low‐cost Li‐free cathode material for high‐rate and long‐life lithium metal batteries.
The successful construction of porphyrin functionalized metallacycle in the confined cavity of mesoporous carbon FDU-16 (3⊂C) is presented in this study. Because of high dispersity of metallacycles within the mesoporous cavities, the stability and activity of porphyrin-containing metallacycles were obviously improved. For example, O generation efficiency of 3⊂C is ca. 6-fold faster than that of free metallaycles in solution. Thus, the resultant hybrid material has been successfully employed as a heterogeneous catalyst for photooxidation of sulfides.
By using Ti3C2T
x
quantum dots as interlayer
spacers, Ti3C2T
x
nanosheets/Ti3C2T
x
quantum dots/RGO (reduced graphene oxide) fiber (M6M3RG1) is prepared by a wet-spinning method; it shows
good capacitance and excellent flexibility. The M6M3RG1 fiber electrode possesses a novel network structure
and a maximum volumetric capacitance of 542 F cm–3, and its capacitance and flexibility are affected by the amount
of Ti3C2T
x
quantum
dots. Also, the Ti3C2T
x
/PEDOT:PSS [poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate)]
fiber (M7P3) is prepared by injecting a homogeneous
suspension of Ti3C2T
x
nanosheets and PEDOT:PSS into a bath of 98 wt % H2SO4. The M6M3RG1 fiber is used
as the positive electrode, and the M7P3 fiber
is used as the negative electrode; a M6M3RG1//M7P3 asymmetric, flexible, solid-state
supercapacitor is assembled in a PVA–H2SO4 gel electrolyte. The assembled device exhibits a volumetric capacitance
of 53.1 F cm–3 and a good cycle stability of 96.6%
after 5000 cycles. It also shows outstanding flexibility and mechanical
properties; for example, the volumetric capacitance has no obvious
change after the device is bent at 90° for 500 times. Moreover,
its voltage window can be expanded to 1.5 V, and a maximum volumetric
energy density of 16.6 mWh cm–3 can be achieved.
This work will open up a new application area for new wearable energy
storage devices based on the Ti3C2T
x
fibers.
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