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Design challenges in the development of circularly polarized luminescence (CPL) materials are focused on balancing the luminescence dissymmetry factor (

A deep-blue OLED based on a novel hot exciton material exhibited an EQEmax of 7.51% with CIE coordinates of (0.154, 0.075).

P-heteroannulation on perylene diimides in one pot is presented. The resulting phosphaperylene diimides demonstrate unique molecular structures with an out-of-plane dipole moment of 8.10 D. Photophysical characterization reveals degenerated LUMO levels as low as -4.4 eV and remarkable absorption redshifts extending to 579 nm. High fluorescence quantum yields (

Manipulating the molecular orbital properties of excited states and the subsequent relaxation processes can greatly alter the emission behaviors of luminophores. Herein we report a vivid example of this, with luminescence conversion from thermally activated delayed fluorescence (TADF) to ultralong room-temperature phosphorescence (URTP) via a facile substituent effect on a rigid benzothiazino phenothiazine tetraoxide (BTPO) core. Pristine BTPO with multiple heteroatoms shows obvious intramolecular charge transfer (ICT) excited states with small exchange energy, featuring TADF. Via delicately functionalizing the BTPO core with peripheral moieties, the excited states of the BTPO derivatives become a hybridized local and charge transfer (HLCT) state in the S1 state and a local excitation (LE) dominated HLCT state in the T1 state, with enlarged energy bandgaps. Upon dispersion in a polymer matrix, the BTPO derivatives exhibit a persistent bright green afterglow with long lifetimes of up to 822 ms and decent quantum yields of up to 11.6%., The decoration of a BTPO core results in a change in the luminescence nature from TADF to URTP. The phosphors in an amorphous PMMA matrix showed monomeric URTP with phosphorescence lifetimes of up to 822 ms and quantum yields of up to 11.6%.

Two diastereoisomers (NTPH-P and NTPH-T1) as a C 2-symmetric triple [5]helicene based on N -annulated triperylene hexaimide were synthesized. Aided by nuclear magnetic resonance spectroscopy (NMR) and theoretical calculations, NTPH-P was assigned to three-blade propeller conformation while NTPH-T1 tended to exhibit twisted conformation with pyrrole ring fusing on a bowl-shaped PDI foil. Characterized by circular dichroism (CD) and circular polarized luminescence (CPL) measurements, the enantiomerically pure NTPH-P exhibited fairly good chiral activities both in the absorption and emission range with dissymmetry factors | g abs| of 4.1×10−3 and | g lum| of 1.2×10−3. The diastereoisomers were further employed as acceptors for organic solar cells with distinct PCEs of 8.11% and 5.24% for NTPH-P and NTPH-T1 based devices, respectively, signifying the prospects in chiroptical electronics by designing molecularly defined aromatics.

Development of highly efficient and stable lateral organic circularly polarized light photodetector is a fundamental prerequisite for realization of circularly polarized light integrated applications. However, chiral semiconductors with helical structure are usually found with intrinsically low field-effect mobilities, which becomes a bottleneck for high-performance and multi-wavelength circularly polarized light detection. To address this problem, here we demonstrate a novel strategy to fabricate multi-wavelength circularly polarized light photodetector based on the donor-acceptor heterojunction, where efficient exciton separation enables chiral acceptor layer to provide differentiated concentration of holes to the channel of organic field-effect transistors. Benefitting from the low defect density at the semiconductor/dielectric interface, the photodetectors exhibit excellent stability, enabling current roll-off of about 3–4% over 500 cycles. The photocurrent dissymmetry value and responsivity for circularly polarized light photodetector in air are 0.24 and 0.28 A W−1, respectively. We further demonstrate circularly polarized light communication based on a real-time circularly polarized light detector by decoding the light signal. As the proof-of-concept, the results hold the promise of large-scale circularly polarized light integrated photonic applications.

The possibility and rate of charge separation (CS) in donor-bridge-acceptor molecules mainly depend on two factors: electronic coupling and solvent effects. The question of how CS occurred in two identical chromophores is fundamental, as it is particularly interesting for potential molecular electronics applications and the photosynthetic reaction centers (RCs). Conjugated bridge definitely plays a crucial role in electronic coupling. To determine the bridge-mediated charge separation dynamics between the two identical chromophores, the isomeric N-annulated perylene diimide dimers (para-BDNP and meta-BDNP) with different conjugated bridge structures have been comparatively investigated in different solvents using femtosecond transient absorption spectra (fs-TA). It is found that the charge separation is disfavored in weak polar solvent, whereas direct spectroscopic signatures of radicals are observed in polar solvents, and the rate of charge separation increases as the solvent polarity increasing. To our surprise, the rate of charge separation in m-BDNP is more than an order of magnitude slower than that in p-BDNP, although there is a larger negative ΔGCS in m-BDNP. The slow CS rate that occurred in m-BDNP mainly results from the intrinsic destructive interference of the wave function through the meta-substituted bridge. The roles of solvent effects in free energy and electronic coupling for charge separation are further identified with quantum calculations.

Cancer immunotherapies rely on one or few specific tumour-associated antigens. However, the adaptive immune system relies on a large and diverse repertoire of antibodies for antigen recognition. Here we report the development and applicability of libraries of immune cells displaying diverse repertoires of chimaeric antigen receptors (CARs) that can recognize non-self antigens and display antigen-dependent clonal expansion, with the expanded population of tumour-specific effector cells leading to long-lasting antitumour responses in mouse models of epithelial tumours. The intravenous injection of synthetic libraries of murine CARs on TET2

Targeted therapeutics for the treatment of coronavirus disease 2019 (COVID-19), especially severe cases, are currently lacking. As macrophages have unique effector functions as a first-line defense against invading pathogens, we genetically armed human macrophages with chimeric antigen receptors (CARs) to reprogram their phagocytic activity against SARS-CoV-2. After investigation of CAR constructs with different intracellular receptor domains, we found that although cytosolic domains from MERTK (CARMERTK) did not trigger antigen-specific cellular phagocytosis or killing effects, unlike those from MEGF10, FcRγ and CD3ζ did, these CARs all mediated similar SARS-CoV-2 clearance in vitro. Notably, we showed that CARMERTK macrophages reduced the virion load without upregulation of proinflammatory cytokine expression. These results suggest that CARMERTK drives an ‘immunologically silent’ scavenger effect in macrophages and pave the way for further investigation of CARs for the treatment of individuals with COVID-19, particularly those with severe cases at a high risk of hyperinflammation.

A functional and effective cell-based immunosurveillance system requires two necessary components: a repertoire of receptors derived from immunoglobulin-like molecules for diverse molecular recognition and a signalling pathway-based activation mechanism for sorting signals and enabling effective activation. Besides the MHC restricted recognition pattern adopt by the adaptive immune cells, such as T cells, and the “missing-self” mechanism discovered in innate immune, such as NK cells, we proposed another novel artificial bionic immune cell system based on a synthetic receptor repertoire and genetic circuits. For this system, a pre-established population of genetically engineered lymphocyte repertoires was developed in which a particular antigen can exclusively activate its specific counter cell, enabling that specific cell to survive and multiply under a specific artificial environment and to destroy particular antigens. Two synthetic patterns were postulated based on CAR receptors and synNotch receptors, in which the antibody library took the place of the antigen-recognition region. The inhibited expression of the inducible caspase-9 suicide gene was coupled with the activation of the synthetic receptor, allowing the lymphocyte repertoire to co-evolve with the dynamic expression of antigens. Synthetic cell repertoire shows significant anti-tumour effect both in vitro and in vivo. Tumour specific killer cells were enriched within one month in vivo even for large repertoire with abundant diversity. In theory, if the diversity of the lymphocyte repertoire is sufficient, then this artificial system can be used for the treatment of any human disease.

The perfect synchronization of maternal immune-endocrine mechanisms and those of the foetus is necessary for a successful pregnancy. In this report, decidual immune cells at the maternal-foetal interface were detected that expressed TIGIT (T cell immunoreceptor with Ig and ITIM domains), which is a co-inhibitory receptor that triggers immunological tolerance. We generated recombinant TIGIT-Fc fusion proteins by linking the extracellular domain of TIGIT and silent Fc fragments. The treatment with TIGIT-Fc of human decidual dendritic cells (dDCs) increased the production of interleukin 10 and induced the dDCs to powerfully polarize the decidual CD4+ T cells towards a classic TH2 phenotype. The administration of TIGIT-Fc to CBA/J pregnant mice at preimplantation induced CD4+ forkhead box P3+ (Foxp3+) regulatory T cells and tolerogenic dendritic cells and increased pregnancy rates in a mouse model of abortive stress. Moreover, we proposed that progesterone play a direct role in the transcriptional regulation of the TIGIT gene in decidual immune cell subsets. The results suggested the therapeutic potential of the TIGIT-Fc fusion protein in reinstating immune tolerance in failing pregnancies.

Doping plays a crucial role in tuning charge transport of organic thermoelectric (TE) materials. A typical n-type organic semiconductors , perylene diimmide (PDI), was used as a dopant to improve the TE performance of PEDOT:PSS films. At 10 wt% PDI content, the electrical conductivity (1500 S cm −1) and Seebeck coefficient (36.7 μV K−1 ) of PEDOT:PSS/PDI films were improved by 20% and 109%, respectively. The doping may arise from the interaction between the lone-pair electrons of nitrogen in PDI and the polarons of PEDOT. This work offers a new though for developing new dopant to tune TE performance of conducting polymers .

The world is experiencing one of the most difficult moments in history with COVID‐19, which has rapidly developed into a worldwide pandemic with a significant health and economic burden. Efforts to fight the virus, including prevention and treatment, have never stopped. However, no specific drugs or treatments have yet been found. Antibody drugs have never been absent in epidemics such as SARS, MERS, HIV, Ebola, and so on in the past two decades. At present, while research on the SARS‐CoV‐2 vaccine is in full swing, antibody drugs are also receiving widespread attention. Several antibody drugs have successfully entered clinical trials and achieved impressive therapeutic effects. Here, we summarize the therapeutic antibodies against SARS‐CoV‐2, as well as the research using ACE2 recombinant protein or ACE2‐Ig fusion protein., Several antibody drugs have successfully entered clinical trials and achieved impressive therapeutic effects. Due to the rapid progress in the field of therapeutic antibodies for COVID‐19 treatment, we summarized the neutralizing antibody drugs and fusion protein drugs that have attracted high attention at present, discussed the existing problems in the current application of antibodies drugs for COVID‐19, and prospected the future research direction in this field.

The first example of sila-annulation onto the perylene diimide core that allows the effective and practical synthesis of both sila- and disilaperylene diimides (Si-PDIs and 2Si-PDIs) in one pot through palladium-catalyzed Si–C bond formation is presented. The corresponding sila-annulated perylene diimides demonstrated exceptional optical properties with noteworthy bathochromic shifts and excellent fluorescence quantum yields. Single crystal analysis revealed almost planar molecular structures and distinct packing arrangements with intense π–π interactions. Their single crystal OFET devices showed good electron mobilities of up to 0.3 cm2 V–1 s–1 under a nitrogen atmosphere.