Albumin-bound paclitaxel dimeric prodrug nanoparticles with tumor Qr redox heterogeneity-triggered drug release for synergistic photothermal/ chemotherapy

In spired by the clinically approved albumin based PTX formulatio n(Abraxa ne)and high-drug-loading dimeric prodrug tactics,herein we report a theranostic HAbraxane-likeH prodrug formulation,which is comprised of human serum albumin(HSA),a paclitaxel(PTX)dimer bridged with thioether liner(PTX2-S),and photosensitizer IR780 iodide.Nanoparticles(NPs)with PTX2-S and IR780 as the core and HSA as the stealth shell are formed.Compared with HSA-based PTX clinical formulation(Abraxane),the dimeric molecules not only constitute the bulk structure of the particles,but also act as crossi ng age nt,thus realizing drug loadi ng content in creasi ng from 6.6 wt.%to 48.7 wt.%with high loadi ng efficie ncy(>90%)and excellent stability in biological conditions.Importa ntly,the thioether lin kage dually resp onds to the tumor redox heteroge neity and the NPs gradually releases the pare nt drug PTX for chemotherapy.Mea nwhile,PTX2-S facilitates the en capsulatio n of IR780 iodide due to their π-π stacki ng interaction and IR780 iodide gen erates spatio-temporal hyperthermia un der light irradiation to kill cancer cells for photothermal therapy.The described craft integrates the biomimetic trait of HSA,high drug loading,tumor redox heterogeneity-initiated on-dema nd drug release,and combi nation therapy into one formulati on and the developed nan oparticles are promising for cancer treatment.

Through-space charge transfer blue polymers containing acridan donor and oxygen-bridged triphenylboron acceptor for highly efficient solution-processed organic light-emitting diodes

Three kinds of through-space charge transfer(TSCT)blue polymers containing non-conjugated polystyrene backbone together with spatially-separated acridan donor and oxygen-bridged triphenylboron acceptors having different substituents of tert-butyl,hydrogen and fluorine are designed and synthesized.The designed TSCT blue polymers possess photoluminescence quantum yields up to 70%in solid-state film,single-triplet energy splitting below 0.1 eV,and typical thermally activated delayed fluorescence(TADF)effect.Meanwhile,the resulting polymers exhibit aggregation-induced emission(AIE)effect with emission intensity increased by up to^27 folds from solution to aggregation state.By changing the substituent of acceptors to tune the charge transfer strength,blue emission with peaks from 444 to 480 nm can be realized for the resulting polymers.Solution-processed organic light-emitting diodes based on the polymers exhibit excellent device performance with Commission Internationale de L’Eclairage(CIE)coordinates of(0.16,0.27),together with the maximum luminous efficiency of 30.7 cd A-1 and maximum external quantum efficiency of 15.0%,which is the best device efficiency for blue TADF polymers.

Self-host yellow iridium dendrimers based on carbazole dendrons: synthesis, characterization and application in solution-processed organic light-emitting diodes

On the basis of different generation carbazole dendrons, a series of self-host yellow Ir dendrimers(Y-G0, Y-G1 and Y-G2)have been successfully synthesized and characterized in detail. It is found that the peripheral dendrons can effectively reduce the intermolecular interactions between emissive Ir cores, as verified by the increased photoluminescence quantum yields and film lifetimes. Among these dendrimers, Y-G2 bearing the second generation dendrons shows the best non-doped device performance,revealing a peak luminous efficiency of 20.2 cd/A. The value is nearly twice that of Y-G0 without any dendrons,which could be further improved to 32.1 cd/A by dispersing Y-G2 into a host matrix. We believe that this work will shed light on the development of highly efficient yellow phosphorescent dendrimers with a self-host strategy.

Novel boron-and sulfur-doped polycyclic aromatic hydrocarbon as multiple resonance emitter for ultrapure blue thermally activated delayed fluorescence polymers

Boron(B)-and sulfur(S)-doped polycyclic aromatic hydrocarbons(PAHs)are developed as a novel kind of multiple resonance emitters for ultrapure blue thermally activated delayed fluorescence(TADF)polymers with narrowband electroluminescence.The combination of electron-deficient B atom and electron-rich S atom in PAH can form an intramolecular push-pull electronic system in a rigid aromatic framework,leading to reduced singlet-triplet energy splitting and limited structure relaxation of excited states.The critical roles of S atom in determining emission properties with respect to the oxygen analogues are in two aspects:(i)reducing energy bandgap to shift emission from human-eye-insensitive ultraviolet zone to blue region,and(ii)promoting reverse intersystem crossing process by heavy-atom effect to activate TADF effect.The resulting polymer containing B,S-doped PAH as emitter and acridan as host exhibits efficient blue electroluminescence at 458 nm with small full-width at halfmaximum of 31 nm,representing the first example for ultrapure TADF polymer with narrowband electroluminescence.