An efficient strategy is reported to achieve rewritable and multi-level security printing based on the emission intensity and lifetime switching caused by manipulating the dynamic ionic coordination of Mn(II) complexes. Confidential information can be repeatedly printed on the fabricated security paper by controlling the dynamic ionic interaction of Mn(II) complexes. Moreover, multilevel security printing has been achieved through dynamically tuning the emission lifetimes of the Mn(II) complexes.
It is still challenging to achieve high-efficiency pure-red
(620–650
nm wavelength) perovskite light-emitting diodes (PeLEDs). Herein,
we report pure-red PeLEDs with Commission Internationale de l’Eclairage
coordinates (0.703, 0.297) meeting the Rec. 2020, an external quantum
efficiency of 20.8%, and a luminance of 3775 cd/m2. This
design is based on the strong quantum confinement CsPbI3 quantum dots (QDs) capped by composite ligands of 3-phenyl-1-propylamine
and tetrabutylammonium iodide. This strategy stabilized the structure
of the strong-confined QDs and reduced the influence of the electric
field-induced Stark effect on the PeLEDs. Furthermore, the exciton
binding energy of the QDs was decreased by the composited ligands
to suppress Auger recombination within the devices. Additionally,
the valence-band maximum of the QDs was lifted to match the hole-transport
layer, thus balancing charge injection in the PeLEDs. Our device also
demonstrated a stable electroluminescence spectrum and a lifetime
of 5.6 times longer than the control device.
It is always a huge challenge to develop novel near-infrared (NIR) phototherapeutic agents suitable for imaging-guided cancer therapy. In order to clarify the positive heavy atom effects on the photodynamic and photothermal efficiencies of phototherapeutic agents, a series of chlorine-, bromide-, or iodine-substituted aza-BODIPYs (B2, B3, and B4, respectively) are designed and synthesized. Among them, B4 exhibits both excellent photodynamic and photothermal effects (singlet oxygen yield of B4 is 1.57 times more than that of B3) and excellent photothermal effects (1.3 °C higher than that of B3). Then, nanoparticles of B4 (IABNs) with excellent biocompatibility are prepared by coating hydrophobic B4 with hydrophilic polymer DSPE-mPEG . IABN exhibits high photostability, excellent biocompatibility, and low dark toxicity both in vivo and in vitro. Furthermore, IABN shows the enhanced photodynamic effect and high photothermal conversion efficiency (34.8%). In addition, the strong fluorescence emission of IABN makes it suitable for fluorescence imaging-guided tumor therapy in vivo. Finally, IABN has successfully healed the Hela tumor-bearing mice under NIR fluorescence imaging- and photothermal imaging-guided synergistic photothermal and photodynamic therapy with low side effects, demonstrating that it is promising for future clinical applications.
We have developed semiconducting polymer nanoparticle-based photosensitizers for O2mapping and enhanced the PDT effect by using fluorescence resonance energy transfer.
Phototherapy, as an important class of noninvasive tumor treatment methods, has attracted extensive research interest. Although a large amount of the near-infrared (NIR) phototherapeutic agents have been reported, the low efficiency, complicated structures, tedious synthetic procedures, and poor photostability limit their practical applications. To solve these problems, herein, a donor−acceptor−donor (D−A−D) type organic phototherapeutic agent (B-3) based on NIR aza-borondipyrromethene (aza-BODIPY) dye has been constructed, which shows the enhanced photothermal conversion efficiency and high singlet oxygen generation ability by simultaneously utilizing intramolecular photoinduced electron transfer (IPET) mechanism and heavy atom effects. After facile encapsulation of B-3 by amphiphilic DSPE−mPEG 5000 and F108, the formed nanoparticles (B-3 NPs) exhibit the excellent photothermal stabilities and reactive oxygen and nitrogen species (RONS) resistance compared with indocyanine green (ICG) proved for theranostic application. Noteworthily, the B-3 NPs can remain outstanding photothermal conversion efficiency (η = 43.0%) as well as continuous singlet oxygen generation ability upon irradiation under a single-wavelength light. Importantly, B-3 NPs can effectively eliminate the tumors with no recurrence via synergistic photothermal/photodynamic therapy under mild condition. The exploration elaborates the photothermal conversion mechanism of small organic compounds and provides a guidance to develop excellent multifunctional NIR phototherapeutic agents for the promising clinical applications.
A novel aggregation- and crystallization-induced emission luminophore (ENPOMe) containing tetraphenylethene and acrylonitrile moieties with high fluorescence efficiency (Φ(F) of up to 0.85) has been easily synthesized. ENPOMe has an exceptionally large two-photon absorption cross section (σ) of 5548 GM, and exhibits striking multi-stimuli-responsive single- and two-photon fluorescence switching with excellent reversibility in the solid state.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.