Visualizing the interfacial-layer-based epitaxial growth process toward organic core-shell architectures.

Organic heterostructures (OHTs) with the desired geometry organization on micro/nanoscale have undergone rapid progress in nanoscience and nanotechnology. However, it is a significant challenge to elucidate the epitaxial-growth process for various OHTs composed of organic units with a lattice mismatching ratio of > 3%, which is unimaginable for inorganic heterostructures. Herein, we have demonstrated a vivid visualization of the morphology evolution of epitaxial-growth based on a doped interfacial-layer, which facilitates the comprehensive understanding of the hierarchical self-assembly of core-shell OHT with precise spatial configuration. Significantly, the barcoded OHT with periodic shells obviously illustrate the shell epitaxial-growth from tips to center parts along the seeded rods for forming the core-shell OHT. Furthermore, the diameter, length, and number of periodic shells were modulated by finely tuning the stoichiometric ratio, crystalline time, and temperature, respectively. This epitaxial-growth process could be generalized to organic systems with facile chemical/structural compatibility for forming the desired OHTs.

Precise Synthesis of Organic Cocrystal Alloys with Full-Spectrum Emission Characteristics for the Stepless Color Changing Display.

Organic luminescent materials are indispensable in optoelectronic displays and solid-state luminescence applications. Compared with single-component, multi-component crystalline materials can improve optoelectronic characteristics. This work forms a series of full-spectrum tunable luminescent charge-transfer (CT) cocrystals ranging from 400 to 800 nm through intermolecular collaborative self-assembly. What is even more interesting is that o-TCP-Cor(x)-Pe(1-x), p-TCP-Cor(x)-Pe(1-x), and o-TCP-AN(x)-TP(1-x) alloys are prepared based on cocrystals by doping strategies, which correspondingly achieve the stepless color change from blue (CIE [0.22, 0.44]) to green (CIE [0.16, 0.14]), from green (CIE [0.27, 0.56]) to orange (CIE [0.58, 0.42]), from yellow (CIE [0.40, 0.57]) to red (CIE [0.65, 0.35]). The work provides an efficient method for precisely synthesizing new luminescent organic semiconductor materials and lays a solid foundation for developing advanced organic solid-state displays.

Peptide-drug conjugates for tumor targeted diagnosis and treatment / 药学学报

Cancer is still one of the major diseases threatening human life and health. At present, how to achieve precise diagnosis and treatment of tumors is the biggest challenge in cancer treatment. Prodrugs use the tumor specificity of targeting molecules to deliver anticancer drugs to tumor sites, which can effectively improve drug bioavailability, therapeutic efficacy and safety, and are currently a hot spot in the research and development of anticancer drugs. The targeting molecules of prodrugs mainly include nucleic acid aptamers, polymers, antibodies, polypeptides, etc. Among them, polypeptides have the advantages of good biocompatibility, controllable degradation performance, high in vivo responsiveness, and simple and easy preparation methods, and are widely used. It is used to construct peptide-drug conjugates (PDC) prodrugs to achieve targeted therapy of tumors. In recent years, with the development of phage peptide library technology and peptide standard solid-phase synthesis technology, more and more targeted peptides have been discovered and effectively synthesized and modified, providing strong support for the development of PDC. This review briefly introduces the types and functions of functional peptides and linkers in PDC, and discusses the application of PDC in chemotherapy, immunotherapy and photodynamic therapy in tumor targeted diagnosis and treatment, and finally summarizes the difficulties faced by PDC drug development.

Icaritin and pyropheophorbide-a self-assembled nanomedicine for enhanced the efficacy of photodynamic tumor therapy by increase the cell autophagy / 药学学报

Autophagy often occurs after cells are attacked by oxidative stress, where damaged structures are phagocytic and degraded into nutrients, thereby reducing oxidative damage, promoting the survival of cancer cells and reducing the therapeutic effect of photodynamic therapy (PDT). However, excessive activation of autophagy can promote cell apoptosis. In this paper, the photosensitizer pyropheophorbide-a (Ppa) was used to produce a large amount of reactive oxygen species (ROS) to achieve the effect of killing cancer cells. At the same time, icaritin (Ica), an autophagy inducer, was used to over-activate autophagy, which transformed the protection of cancer cells into the promotion of cancer cell apoptosis, so as to improve the effect of photodynamic therapy. In this study, the interaction force between Ica and Ppa was exploited to successfully construct a self-assembled nanomedicine IP with good stability and high drug load. The synthesis method is simple, through using the drug itself as a carrier, and the loading capacity (LA) of Ica and Ppa can be increased to 83.53% and 16.45% without introducing potential biosafety risks of nanocarriers. Compared with free Ppa, self-assembled nanomedicine IP showed superior performance in cellular uptake and reactive oxygen species production. In addition, the self-assembled nanomedicine IP can reverse the protective autophagy induced by PDT by activating the autophagy of tumor cells, and facilitate apoptosis and antitumor coordination, which significantly improves the antitumor activity of PDT.

Design and Growth of Branched Organic Crystals: Recent Advances and Future Applications.

The rapid development of information technology has resulted in a growing demand for low-dimensional photonic materials. Organic semiconductor materials play an important role in various photonic devices due to their adjustable physicochemical properties, while individual organic crystals do not exhibit the desired performance due to the limitations of their simple structure. Branched organic crystals with inherent multichannel characteristics based on π-conjugated molecules are favorable components in optoelectronics. However, the preparation of branched organic crystals still faces great challenges before they can be applied in integrated optoelectronic devices. In this Review, the development and representative examples of branched organic crystals in terms of molecular design, synthesis, and advanced applications are discussed. We also provide a summary and outlook for the direction of future research on branched organic crystals as excellent candidates in photonic integrated circuits.

Efficient All-Inorganic Perovskite Light-Emitting Diodes with Cesium Tungsten Bronze as a Hole-Transporting Layer.

The realization of high-performance optoelectronic devices requires excellent charge-transporting layers and efficient carrier recombination. Herein, we synthesized cesium tungsten bronze (Cs0.32WO3) nanocrystals and utilized them as the hole-transporting material to fabricate all-inorganic perovskite light-emitting diodes (PeLEDs). Due to the excellent carrier balance characteristics via comparison between the hole-only device and electron-only device, the all-inorganic PeLEDs with CsPbBr3 as the light-emitting layer present the maximum current efficiency of 31.51 cd/A and external quantum efficiency (EQE) of 8.48%, which are self-evidently enhanced compared with the PEDOT:PSS (14.78 cd/A, 4.03%) and WO3 (24.75 cd/A, 6.18%) based devices. Considering the remarkably improved device performance, the proposed HTL of Cs0.32WO3 is promising, acting as a favorable building block for high-efficiency light-emitting devices.

Effect of Schizonepetae Herba and Saposhnikoviae Radix on expression of AQP4 and AQP8 in colonic mucosa of rats with ulcerative colitis / 中国中药杂志

The aim of this paper was to investigate the effect of Schizonepetae Herba and Saposhnikoviae Radix(wind medicine) on the expression of AQP4 and AQP8 in colonic mucosa in rats with ulcerative colitis(UC). A total of 35 healthy SD male rats were randomly divided into normal group(gavaged with normal saline), DSS model group, as well as low, middle, and high dose wind medicine groups(Schizonepeta and Saposhnikovia 1∶1, gavaged at dosages of 6, 12, and 24 g·kg~(-1)·d~(-1)), with 7 in each group. UC rat model was established by free drinking of 3% dextran sulphate sodium(DSS) solution for 10 days. At the end of the 10 th day after the treatment, mice were put to death to collect colonic mucosa. The length of colon was measured; the colonic mucosal injury index(CMDI) and pathological changes of colon were observed. ELISA method was used for measuring the content of serum IL-1, IL-8, and immunohistochemical method was used to measure AQP4, AQP8 protein expressions in colon mucosa. The expressions of AQP4, AQP8 mRNA were measured by Real-time PCR. As compared with the normal group, the length of colon tissue was significantly reduced(P<0.01), CMDI scores and pathological scores were significantly increased(P<0.01), the levels of serum IL-1 and IL-8 were significantly increased(P<0.05) in model group; the immunohistochemical results showed that the protein expressions of AQP4, AQP8 were lower; the color was light yellow or brown; AQP4, AQP8 mRNA expressions in colon mucosa were significantly decreased in model group(P<0.01). CMDI scores, pathological scores, and the levels of serum IL-1, IL-8 in high, middle, low dose wind medicine groups were obvious lower than those in the model group(P<0.01 or P<0.05); the protein expressions of AQP4, AQP8 were higher; the color was chocolate brown or dark brown; the length of colon tissue, and the expressions of AQP4, AQP8 mRNA were obvious higher in wind medicine groups(P<0.01 or P<0.05). Schizonepetae Herba and Saposhnikoviae Radix could significantly improve the symptoms and histopathology of UC model rats and accelerate the intestinal mucosal healing. The mechanism may be related with up-regulating the expression level of AQP4 and AQP8 in colonic mucosa.

Tumor microenvironment responsive biomimetic nanoparticles for photodynamic tumor therapy / 药学学报

Inspired by the coordination effects between imidazole and metal ions in hemoglobin, biomimetic nanoparticles were constructed for photodynamic tumor therapy. The photosensitizer of protoporphyrin IX (PpIX) was modified with histidine, which could be self-assembled with Zn2+ to obtain the biomimetic nanoparticles (NPs). Under the conditions of high glutathione and low pH, the biomimetic nanoparticles could be degraded and released for enhanced photodynamic tumor therapy. The structures of NPs were characterized by dynamic light scattering (DLS), UV-visible spectrophotometer (UV-Vis), fluorescence microscope and transmission electron microscope (TEM). The reactive oxygen species (ROS) production ability of NPs was measured by singlet oxygen sensor green (SOSG) test kit. Mouse breast cancer cell lines (4T1 cells) were employed to investigate the subcellular organelle distribution and cytotoxicity of NPs. These results confirmed that NPs possessed a good dispersibility and stability with a uniform structure and particle size at 165 nm. Moreover, MTT assay and live/dead cell staining assay demonstrated that NPs could inhibit the proliferation of 4T1 cells and exhibit a good biocompatability. This research would promote the construction of intelligent biomedicine for tumor precision therapy.

Design and in vitro evaluation of delivery systems for co-delivery of siRNA and proteins by mimetic exosomes / 药学学报

To prepare the mimetic exosomes and co-delivery proteins and nucleic acids, and achieve efficient and safe co-delivery of multi-component drugs, an optimized formulation was designed by modifying a polylactic acid-glycolic acid copolymer (PLGA) matrix with a cationic lipid excipient dioleyl trimethylammonium propane (DOTAP), and a PLGA/DOTAP nanoparticles packaged protein and nucleic acid was prepared by double emulsion method, and the outermost membrane structure prepared by reverse phase evaporation method and consists of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC), 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC), 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC), cholesterol and membrane proteins. The structure of the mimetic exosomes is formed by ultrasonic dispersion and extrusion, and analyzed its characteristics and nature of the transfer effect. The size of mimetic exosomes was about 156.13 nm, with negative charge (-18.23 ± 0.57 mV), and it could efficiently co-transfer protein and siRNA, and siRNA could effectively inhibit the expression of target gene Trim28. The mimetic exosomes simulate the structure of exosomes and achieve safe and efficient co-delivery of multi-component drugs.

Research Progress on Complex Kinship Analysis / 法医学杂志

Complex kinship analysis refers to a kind of special kinship analysis taken for the purpose of personal identification or other issues in civil or criminal cases because the father or （and） mother is dead, or cannot participate in the analysis for other reasons. Due to the absence of significant appraised persons in this kind of kinship analysis, grandparents, siblings or collateral relatives are required to participate in the analysis. Complex kinship analysis is widely used and the demand is increasing year by year. This paper analyzes the main types of complex kinships, the genetic markers of complex kinship analysis and their advantages and disadvantages and the calculation methods for complex kinship analysis by referring to the relevant literatures at home and abroad in recent years. At the same time, the shortcomings of the present research on complex kinship and its future development are prospected.

Determination of Electrocution Using Fourier Transform Infrared Microspectroscopy and Machine Learning Algorithm / 法医学杂志

Objective To analyze the differences among electrical damage, burns and abrasions in pig skin using Fourier transform infrared microspectroscopy （FTIR-MSP） combined with machine learning algorithm, to construct three kinds of skin injury determination models and select characteristic markers of electric injuries, in order to provide a new method for skin electric mark identification. Methods Models of electrical damage, burns and abrasions in pig skin were established. Morphological changes of different injuries were examined using traditional HE staining. The FTIR-MSP was used to detect the epidermal cell spectrum. Principal component method and partial least squares method were used to analyze the injury classification. Linear discriminant and support vector machine were used to construct the classification model, and factor loading was used to select the characteristic markers. Results Compared with the control group, the epidermal cells of the electrical damage group, burn group and abrasion group showed polarization, which was more obvious in the electrical damage group and burn group. Different types of damage was distinguished by principal component and partial least squares method. Linear discriminant and support vector machine models could effectively diagnose different damages. The absorption peaks at 2 923 cm-1, 2 854 cm-1, 1 623 cm-1, and 1 535 cm-1 showed significant differences in different injury groups. The peak intensity of electrical injury's 2 923 cm-1 absorption peak was the highest. Conclusion FTIR-MSP combined with machine learning algorithm provides a new technique to diagnose skin electrical damage and identification electrocution.

Network pharmacological study of Schizonepetae Herba and Saposhnikoviae Radix in treatment of ulcerative colitis / 中国中药杂志

The aim of this paper was to screen the active targets of Schizonepetae Herba and Saposhnikoviae Radix in the treatment of ulcerative colitis by means of network pharmacology,and to investigate their mechanism of action. The effective components of Schizonepetae Herba and Saposhnikoviae Radix were screened out by traditional Chinese medicine systematic pharmacological( TCMSP)database,with oral bioavilability( OB) ≥30% and drug-like( DL) ≥18% selected as the thresholds. Target PPI network was built between the main components and their corresponding targets. One hundred and eighty-two human genes corresponding to the medicine target sites were obtained from Uniprot database; 3 874 genes corresponding to ulcerative colitis were obtained from Genecard database.A total of 115 intersection genes were screened from disease genes and medicine genes,and the PPI interaction analysis was conducted by using String tool. Disease-target PPI network was drawn by using Cytoscape software,and component-target-disease network was constructed. One hundred and eight nodes and 1 882 connections were found,and then Cytoscape software was used to merge the networks and filter the core network for gene GO function analysis and KEGG pathway enrichment analysis. The mechanism of Schizonepetae Herba and Saposhnikoviae Radix was then verified by animal experiment. Gene GO functional analysis suggested that biological process,molecular functions and cell components were involved,and it was found that ulcerative colitis might be related to transcription factor activity,and cytokine receptor binding,etc. Gene KEGG pathway enrichment analysis showed that the mechanism of ulcerative colitis might be associated with TNF and Toll-like receptors( TLRs) signaling pathway-mediated cytoinflammatory factors interleukin-1( IL-1) and interleukin-6( IL6). The possible mechanism of the effective components of Schizonepetae Herba and Saposhnikoviae Radix in treating ulcerative colitis might be related to intervening the cytokine receptor binding of TNF and TLRs signaling pathways,reducing the transcription of nuclear factor-kappaB( NF-κB),and inhibiting the secretion of intestinal inflammatory factors IL-1 and IL-6.

Quantitative Expression of RNA from Frozen Organs and Formaldehyde-fixed and Paraffin-embedded Tissues / 法医学杂志

Objective Quantitative analysis and comparison of the expression of ribonucleic acid （RNA） from frozen organs and formaldehyde-fixed and paraffin-embedded （FFPE） tissues. Methods Frozen specimens of human brain, myocardium and liver tissues as well as FFPE samples at different postmortem intervals were collected and mass concentration of RNA was extracted and detected. Reverse transcription-quantitative polymerase chain reaction （RT-qPCR） technology was used to analyze the amplification efficiency and relative expression of each RNA marker. Results The mass concentration and integrity of RNA extracted from FFPE samples were relatively low compared with frozen specimens. The amplification efficiency of RNA markers was related with RNA species and the length of amplification products. Among them, glyceraldehyde-3-phosphate dehydrogenase （GAPDH） and β-actin （ACTB） with relatively long amplification products failed to achieve optimal amplification efficiency, whereas 5S ribosomal RNA （5S rRNA） achieved ideal amplification efficiency and showed quite stable expression across various tissues, therefore it was chosen as internal reference marker. The expression quantity of GAPDH and ACTB in frozen specimens with longer postmortem intervals and in FFPE samples with relatively long amplification products was decreased. The expressions of tissue-specific microRNAs （miRNAs）, GAPDH and ACTB with relatively short amplification products had consistency in the same tissues and FFPE samples. Conclusion Through standardizing the RT-qPCR experiment, selecting the appropriate RNA marker and designing primers of appropriate product length, RNA expression levels of FFPE samples can be accurately quantified.

Analysis of Forensic Sciences Literature in SCIE from 2008 to 2017 / 法医学杂志

OBJECTIVES@#To analyze the literature on forensic sciences indexed in Science Citation Index Expanded （SCIE） in recent 10 years, and to understand the research status, characteristics and trends in the field of forensic sciences.@*METHODS@#Literature on forensic sciences from 2008 to 2017 in Web of Science （WoS） was retrieved. The documents number and geographical distribution, document types, source titles, organizations, research areas, authors, funding agencies, and the high cited articles were detected. The impact factors （IF） of journals were retrieved in Journal Citation Reports （JCR）. The data were analyzed with descriptive statistics.@*RESULTS@#From 2008 to 2017, there were 21 001 documents on forensic sciences in SCIE. The main document type was articles, with English as the major language. With regards to research areas, pathology has the largest number of papers worldwide, and genetics and heredity has the largest number of publications in mainland China. Among the 18 journals where the documents was published, Forensic Science International ranks the first on publication count, and Forensic Science International Genetics has the highest IF （5.637） in the JCR 2017. In 2017, the number of papers from mainland China increased by 48.50% compared with 2016, which was higher than the global increase （32.63%） and the top-5 countries in terms of number of publications （the US, Germany, the UK, Australia, Italy）. The average document count per organization is 1.98 worldwide and 1.17 in mainland China, respectively. The publication number per author is 0.53 worldwide and 0.36 in mainland China, respectively. Around 28.17% of the publications were funded, with National Natural Science Foundation of China （NSFC） as the Top 1 funding agency （192 papers）. Among the documents with citations, the most cited publication has been cited for 366 times.@*CONCLUSIONS@#The yearly numbers of publications on forensic sciences are increasing during recent 10 years. Focusing on the mainland China, there would be more high-quality papers with the steady funding of NSFC.

Controlled synthesis of organic single-crystalline nanowires via the synergy approach of the bottom-up/top-down processes.

The controlled fabrication of organic single-crystalline nanowires (OSCNWs) with a uniform diameter in the nanoscale via the bottom-up approach, which is just based on weak intermolecular interaction, is a great challenge. Herein, we utilize the synergy approach of the bottom-up and the top-down processes to fabricate OSCNWs with diameters of 120 ± 10 nm through stepwise evolution processes. Specifically, the evolution processes vary from the self-assembled organic micro-rods with a quadrangular pyramid-like end-structure bounded with {111}s and {11-1}s crystal planes to the "top-down" synthesized organic micro-rods with the flat cross-sectional {002}s plane, to the organic micro-tubes with a wall thickness of ∼115 nm, and finally to the organic nanowires. Notably, the anisotropic etching process caused by the protic solvent molecules (such as ethanol) is crucial for the evolution of the morphology throughout the whole top-down process. Therefore, our demonstration opens a new avenue for the controlled-fabrication of organic nanowires, and also contributes to the development of nanowire-based organic optoelectronics such as organic nanowire lasers.

Methodological research of RNA extraction and quantitative analysis of long non-coding RNA from formalin-fixed paraffin-embedded human brain specimens / 上海交通大学学报（医学版）

Objective·To compare the quality of RNA extracted from fresh and formalin-fixed paraffin-embedded (FFPE) brain tissues and to explore the long non-coding RNA (IncRNA) expression level.Methods·FFPE samples stored under various conditions and paired frozen brain tissues were collected and total RNA qualities were then detected.Amplification efficiency (AE) and expression stability of each RNA marker were calculated and analyzed based on real-time quantitative PCR.After selecting reference biomarkers,normalized △ Ct values of candidate makers within different amplicon size were measured to assess the possibility of lncRNA quantification in FFPE tissues.Results·The purity of RNA extracted from FFPE was relatively high,but the RNA integrity was lower than fresh samples.All biomarkers were successfully amplified and amplification efficiencies of long-chain RNA markers were correlated with amplicon sizes,sample treatment and preservation conditions,namely temperature and storage time.5S,miR-9 and miR 125b achieved optimal AE and showed quite stable expression in all specimens,therefore they were chosen as control markers.Compared with fresh samples,the △ Ct values of only 2 lncRNA (HAR1F and MALAT1-L,whose amplicon size were both higher than 200 bp,respectively) increased in the FFPE samples kept in 4 ℃,while in FFPE tissues kept in room temperature,increments of the △ Ct values were significant for most target genes except for short amplicon markers (＜60 bp),which showed consistently stable expression in all brain specimens.Conclusion·RNA integrity is affected by sample treatment and preservation conditions,but IncRNA expression levels in FFPE tissues can be accurately quantificated by using optimal amplicon sizes and considerable reference markers.

Infrared Spectral Characteristics of Electrical Injuries on Swine Skin Caused by Different Voltages Based on Machine Learning Algorithms / 法医学杂志

Objective To explore infrared spectrum characteristics of different voltages induced electrical injuries on swine skin by using Fourier transform infrared-microspectroscopy (FTIR-MSP) combined with machine learning algorithms, thus to provide a reference to the identification of electrical skin injuries caused by different voltages.Methods Electrical skin injury model was established on swines.The skin was exposed to 110 V, 220 V and 380 V electric shock for 30 s and then samples were took, with normal skin tissues around the injuries as the control.Combined with the results of continuous section HE staining, the FTIR-MSP spectral data of the corresponding skin tissues were acquired.With the combination of machine learning algorithms such as principal component analysis (PCA) and partial least squares-discriminant analysis (PLS-DA), different spectral bands were selected (full band 4 000-1 000 cm-1and sub-bands 4 000-3 600 cm-1, 3 600-2 800 cm-1, 2 800-1 800 cm-1, and 1 800-1 000 cm-1), and various pretreatment methods were used such as orthogonal signal correction (OSC), standard normal variables (SNV), multivariate scatter correction (MSC), normalization, and smoothing.Thus, the model was optimized, and the classification effects were compared.Results Compared with simple spectrum analysis, PCA seemed to be better at distinguishing electrical shock groups from the control, but was not able to distinguish different voltages induced groups.PLS-DA based on the 3 600-2 800 cm-1band was used to identify the different voltages induced skin injuries.The OSC could further optimize the robustness of the 3 600-2 800 cm-1band model.Conclusion It is feasible to identify electrical skin injuries caused by different voltages by using FTIR-MSP technique along with machine learning algorithms.

High performance blue quantum dot light-emitting diodes employing polyethylenimine ethoxylated as the interfacial modifier.

Efficient electron-injection into the emitting layer (EML) plays a pivotal role in the fabrication of high performance blue quantum dot light-emitting diodes (QLEDs). Herein, we reduce the electron-transporting barrier at the ITO/ETL (electron-transporting layer) interface from 0.7 eV to 0.4 eV by spin-coating a polyethylenimine ethoxylated (PEIE) film (8 nm) on the ITO substrate. Meanwhile, the electron-injection barrier was reduced from 0.5 to 0.1 eV at the ETL/QD interface by employing the incorporation of PEIE (0.1 wt%) into a ZnO layer. These above two interfacial modifications jointly decrease the electron barrier and make the electron transportation easier. As a result, the optimized QLEDs with the 460 nm emission peak exhibit a maximum external quantum efficiency (EQE) of 7.85%, which is enhanced by 1.4 fold compared with the reference device (5.68%). It is demonstrated that the facile interfacial modification by the organic polymer PEIE contributes to the fabrication of high-efficiency blue QLEDs.

Polymer as an Additive in the Emitting Layer for High-Performance Quantum Dot Light-Emitting Diodes.

A facile but effective method is proposed to improve the performance of quantum dot light-emitting diodes (QLEDs) by incorporating a polymer, poly(9-vinlycarbazole) (PVK), as an additive into the CdSe/CdS/ZnS quantum dot (QD) emitting layer (EML). It is found that the charge balance of the device with the PVK-added EML was greatly improved. In addition, the film morphology of the hole-transporting layer (HTL) which is adjacent to the EML, is substantially improved. The surface roughness of the HTL is reduced from 5.87 to 1.38 nm, which promises a good contact between the HTL and the EML, resulting in low leakage current. With the improved charge balance and morphology, a maximum external quantum efficiency (EQE) of 16.8% corresponding to the current efficiency of 19.0 cd/A is achievable in the red QLEDs. The EQE is 1.6 times as high as that (10.5%) of the reference QLED, comprising a pure QD EML. This work demonstrates that incorporating some polymer molecules into the QD EML as additives could be a facile route toward high-performance QLEDs.

White-Emissive Self-Assembled Organic Microcrystals.

Organic semiconductor micro-/nanocrystals with regular shapes have been demonstrated for many applications, such as organic field-effect transistors, organic waveguide devices, organic solid-state lasers, and therefore are inherently ideal building blocks for the key circuits in the next generation of miniaturized optoelectronics. In the study, blue-emissive organic molecules of 1,4-bis(2-methylstyryl)benzene (o-MSB) can assemble into rectangular microcrystals at a large scale via the room-temperature solution-exchange method. Because of the Förster resonance energy transfer, the energy of the absorbed photons by the host matrix organic molecules of o-MSB can directly transfer to the dopant organic molecules of tetracene or 1,2:8,9-dibenzopentacene (DBP), which then emit visible photons in different colors from blue to green, and to yellow. More impressively, by modulating the doping molar ratios of DBP to o-MSB, bright white-emissive organic microcrystals with well-preserved rectangular morphology can be successfully achieved with a low doping ratio of 1.5%. These self-assembled organic semiconductor microcrystals with multicolor emissions can be the white-light sources for the integrated optical circuits at micro-/nanoscale.