Screening, Characterization and Evaluation of Mangiferin Polymorphs

Mangiferin is a compound with many pharmacological activities and exists in many natural products.Anhydrous and hydrate of mangiferin have been reported separately in two literatures,but the polymorphism of this compound has not been realized until this paper.In this study,polymorph screening of mangiferin has been carried out and five forms have been obtained including three new forms never reported.Several solid state characterization methods,such as powder X-ray diffraction,differential scanning calorimetry and thermogravimetry,are used to identify and characterize all of mangiferin forms.The comparison of the crystallographic data and hirshfeld surface analysis were first reported for mangiferin anhydrous and hydrate.Furthermore,the studies on stability,transformation and solubility have been undertaken,the results prompt that form V can be used as the dominant polymorph for the development of innovative pharmaceuticals.

Anti-inflammatory Effects and Mechanisms of Rhein, an Anthraquinone Compound, and Its Applications in Treating Arthritis: A Review

Inflammation is a defensive response of living tissues to damaging agents,which exists in two forms,acute inflammation and chronic inflammation,and chronic inflammation is closely related to arthritis.Currently,the commonly prescribed anti-inflammatory medications are greatly limited by high incidence of gastrointestinal erosions in the clinical applications.Rhein,a bioactive constituent of anthraquinone,exhibits excellent anti-inflammatory activities and therapeutic effects on arthritis with less gastrointestinal damages.Although there are numbers of studies on anti-inflammatory effects and mechanisms of rhein in the last few decades,to the best of our knowledge,only a few review articles pay attention to the interactive relationships of rhein on multiple inflammatory signaling pathways and cellular processes from a comprehensive perspective.Herein,we summarized anti-inflammatory effects and mechanisms of rhein and its practical applications in the treatment of arthritis,thereby providing a reference for its basic researches and clinical applications.

Room-Temperature Magnetism of Ceria Nanocubes by Inductively Transferring Electrons to Ce Atoms from Nearby Oxygen Vacancy

Ceria(CeO_2) nanocubes were synthesized by a hydrothermal method and weak ferromagnetism was observed in room temperature. After ultraviolet irradiation, the saturation magnetization was significantly enhanced from*3.18×10^(-3) to *1.89×10^(-2) emug^(-1). This is due to the increase of oxygen vacancies in CeO_2 structure which was confirmed by X-ray photoelectron spectra. The first-principle calculation with Vienna ab-initio simulation package was used to illustrate the enhanced ferromagnetism mechanism after calculating the density of states(DOSs) and partial density of states(PDOSs) of CeO_2 without and with different oxygen vacancies. It was found that the increase of oxygen vacancies will enlarge the PDOSs of Ce 4f orbital and DOSs. Two electrons in one oxygen vacancy are respectively excited to 4f orbital of two Ce atoms neighboring the vacancy, making these electron spin directions on 4f orbitals of these two Ce atoms parallel. This superexchange interaction leads to the formation of ferromagnetism in CeO_2 at room temperature. Our work indicates that ultraviolet irradiation is an effective method to enhance the magnetism of CeO_2 nanocube, and the firstprinciple calculation can understand well the enhanced magnetism.

Preparation and Certification of a New Salvianolic Acid A Reference Material for Food and Drug Research

Salvianolic acid A(Sal A),a water-soluble ingredient in Danshen,has various biological activities.Sal A and its impurities have similar physical and chemical properties,as well as strong reducibility;therefore,they are difficult to prepare and purify.In this study,high-purity Sal A was obtained by purification of sephadex chromatography and preparative chromatography.Furthermore,HPLC-DAD tandem ECD and HPLC-DAD tandem MS methods were used for non-volatile organic impurity analysis,ICP-MS method was used for non-volatile inorganic impurities and mass balance method and quantitative nuclear magnetic resonance were employed to certify the product.The structures of Sal A and its relative impurities were validated by nuclear magnetic resonance spectroscopy and mass spectrometry,and their contents were quantified as well.Following the principles of ISO Guides 34:2009 and 35:2005,a Sal A reference material was certified,covering homogeneity studies,stability studies,characterization,and uncertainty estimations.

Investigation on Agronomic Characters of Dwarf Mutant 778 in Broomcorn Millet(Panicum miliaceum L.)and Analysis of Its Sensitivity to GA

In order to investigate the differences between agronomic traits of dwarf mutant and original material 260 and whether the cause of dwarf is related to GA synthesis or signaling pathway,this experiment used dwarf mutant 778 and its original material 260 as experimental materials.Morphological observation and determination were performed for agronomic traits on plant height,ear length,internode length,internode number,seed length,seed width and number of seeds in different growth periods and different concentrations.The plants were treated by GA spraying,and the changes of plant height,root length,stem width,leaf length and leaf width were measured.The results are as follows:①The plant height of the dwarf mutant material was significantly different from that of the original high material,which was mainly caused by the difference between above-ground basal part and the length of the first and second elongation joints.②Comparing and analyzing the differences of traits between dwarf mutant material 778 and original high material 260,it was found that the plant height,ear length,internode number,grain number per ear and internode length of dwarf mutant 778 were significantly lower than that of high stalk 260(P<0.01),and the seed length of dwarf mutant 778 was significantly higher than that of high stalk 260(P<0.05).③Different concentrations of gibberellin(0,50,100,200 mg/L)had no significant effect on plant height and root length of dwarf mutant 778(P>0.05).Different concentrations of gibberellin had significant effects on plant height,root length and sensitivity coefficient of high stalk 260(P<0.05).And compared with the control group,all high materials 260 treated with different concentrations of gibberellin performed differently in plant morphology and growth potential.④Under the conditions of 100 and 200 mg/L GA,the difference of plant height between the dwarf mutant and the high stalk control decreased with time,and there was no difference at the end.There were no differences in sensitivity coefficient GRI between different concentrations of gibberellin treatment groups,indicating that the external gibberellin could restore the scorpion dwarf mutant to the original high stalk,and the gene that causes the mutation might be related with the gibberellin synthesis pathway.

Heptagonal intramolecular-lock strategy enables high-performance thermally activated delayed fluorescence emitters

The development of highly efficient thermally activated delayed fluorescence(TADF)emitters is persistently pursued for the application of organic light-emitting diodes(OLED)in full-colour display and solid-state lighting.Herein,we present a heptagonal intramolecular-lock strategy to design high-performance TADF emitters.As a proof-of-concept,a new type of tribenzotropone(TBP)acceptor has been designed and synthesized by a cascade decarboxylative cyclization of aryl oxoacetic acid derivative with biphenyl boronic acid.Compared with the unlocked benzophenone(BP)acceptor,the TBP acceptor has a highly twisted heptagonal geometry with moderate rigidity and flexibility,which enables a high-performance TADF emitter with a small single-triplet energy gap(ΔE_(ST))of 0.04 e V,a high photoluminescence quantum yield(Φ_(PL))of 99% and a large horizontal orientation factor(Θ_(//))of 84.0%.Consequently,highly efficient OLEDs with an external quantum efficiency as high as 33.8% are assembled,which is significantly higher than those of DPAC-BP with a highly rotatable BP acceptor(23.8%)as well as DPACFO with a rigid fluorenone(FO)acceptor(6.9%).

平面/体异质结结构全色倍增型有机光电探测器

宽带有机光电探测器(OPDs)可以集成到各种可穿戴设备中,在健康监测等领域显示出巨大的应用潜力.这里,我们以酞菁铅(PbPc)和富勒烯(C70)小分子分别作为给体和受体,基于MoO_(3)俘获电子辅助空穴隧道注入的机制实现了高性能宽带倍增型有机光电探测器(PM-OPDs).为了控制PbPc分子的晶相结构,我们分别制备了PbPc:C70体异质结(BHJ)和PbPc/C70平面异质结(PHJ)器件.可以看出,PHJ器件表现出更强的近红外吸收特性,即更有利于PbPc分子形成三斜相结构.我们进一步使用具有吸收互补特性的材料(PbPc和SubPc)作为有源层,采用PHJ/BHJ混合异质结结构,制备了在300–1000 nm范围内平坦的全色PM-OPDs.在-8 V反向偏压下,制得的全色PM-OPDs在整个光谱响应范围内的外量子效率都超过1000%.最后,我们在聚对苯二甲酸乙二醇酯基板上制备了柔性全色PM-OPDs,并成功地实现了人体脉搏信号的检测.本文通过设计器件结构和选择合适的材料,为获得高性能全色PM-OPDs提供了一种新策略.

Cocrystal virtual screening based on the XGBoost machine learning model

Co-crystal formation can improve the physicochemical properties of a compound,thus enhancing its druggability.Therefore,artificial intelligence-based co-crystal virtual screening in the early stage of drug development has attracted extensive attention from researchers.However,the complexity of developing and applying algorithms hinders it wide application.This study presents a data-driven co-crystal prediction method based on the XGBoost machine learning model of the scikit-learn package.The simplified molecular input line entry specification(SMILES)information of two compounds is simply inputted to determine whether a co-crystal can be formed.The data set includs the co-crystal records presented in the Cambridge Structural Database(CSD)and the records of no co-crystal formation from extant literature and experiments.RDKit molecular descriptors are adopted as the features of a compound in the data set.The developed model shows excellent performance in the proposed co-crystal training and validation sets with high accuracy,sensitivity,and F1 score.The prediction success rate of the model exceeds 90%.The model therefore provides a simple and feasible scheme for designing and screening co-crystal drugs efficiently and accurately.

An innovative rhein-matrine cocrystal: Synthesis, characterization,formation mechanism and pharmacokinetic study

Rhein(Rhe), an anthraquinone derivative, exhibits excellent anti-inflammatory effects and other pharmacological activities, but its clinical application remains limited due to poor solubility. The present work aims at the improvement of solubility and oral bioavailability of Rhe through cocrystal formation. For this purpose, Rhe and matrine(Mat) were selected as pharmaceutical ingredient(API) and cocrystal former(CCF), respectively, and the Rhe-Mat cocrystal was synthesized and characterized by single crystal X-ray diffraction(SXRD), powder X-ray diffraction(PXRD), thermogravimetric analysis(TGA), differential scanning calorimetry(DSC). The formation mechanism of Rhe-Mat cocrystal was elucidated by molecular surface electrostatic potential(MSEP). It is worth mentioning that the 50-fold increment of dissolution in vitro was observed in pure water in the form of Rhe-Mat cocrystal. Furthermore, the in vivo studies revealed that Rhe-Mat cocrystal indicated the faster absorption rate and the higher peak blood concentration than the pure Rhe. Hence, it can be concluded that current study successfully improved the solubility and oral bioavailability of Rhe.

Towards Efficient Blue DelayedFluorescence Molecules by Modulating Torsion Angle Between Electron Donor and Acceptor

Constructing blue thermally activated delayedfluorescence materials for high-performance organic light-emitting diodes(OLEDs)remains challenging due to the intrinsically strong intramolecular charge transfer nature of the nearly orthogonal connection of electron donor(D)and acceptor(A),which results in long-wavelength emission.Herein,an effective delayed-fluorescence design strategy of modulating D–A torsion angles is proposed and efficient sky-blue,pure-blue,and deep-blue delayed-fluorescence molecules consisting of a xanthenone acceptor and carbazole-based donors are created by decreasing the torsion angles.They exhibit strong delayed fluorescence with high photoluminescence quantum yields of 85–94%in doped films,and their delayed-fluorescence lifetimes are elongated from 1.0 to 27.6μs as the torsion angles decrease.These molecules can function as excellent emitters in OLEDs,providing efficient electroluminescence peaking at 442 nm(CIEx,y=0.15,0.08),462 nm(CIEx,y=0.15,0.18),and 482 nm(CIEx,y=0.17,0.30)with state-of-the-art external quantum efficiencies of up to 22.2%,33.7%,and 32.1%,respectively,demonstrating the proposed molecular design for efficient blue delayed-fluorescence molecules is successful and promising.

An efficient aggregation-enhanced delayed fluorescence luminogen created with spiro donors and carbonyl acceptor for applications as an emitter and sensitizer in high-performance organic light-emitting diodes

Organic light-emitting diodes(OLEDs)fabricated using organic thermally activated delayed fluorescence materials as sensitizers have recently achieved significant advancements,but the serious efficiency roll-offs are still troublesome in most cases.Herein,a tailor-made multifunctional luminogen SBF-BP-SFAC containing 9,9′-spirobifluorene(SBF)and spiro[acridine-9,9-fluorene](SFAC)as electron donors and carbonyl as an electron acceptor is synthesized and characterized.SBF-BPSFAC has the advantages of high thermal stability,aggregation-enhanced delayed fluorescence,and balanced carrier transport ability,and prefers horizontal dipole orientation.Highly efficient OLEDs employing SBF-BP-SFAC as an emitter radiate intense cyan light with outstanding external quantum efficiencies(ηexts)of up to 30.6%.SBF-BP-SFAC can also serve as an excellent sensitizer for orange fluorescence,phosphorescence,and delayed fluorescence materials,providing excellent η exts of up to 30.3% with very small efficiency roll-offs due to the fast Förster energy transfer as well as exciton annihilation suppression by bulky spiro donors.These outstanding performances demonstrate the great potential of SBF-BP-SFAC as an emitter and sensitizer for OLEDs.

Spatial distribution and sources of soil heavy metals in the outskirts of Yixing City,Jiangsu Province,China

City outskirts serve as the concentration centers for the pollutants discharged from various sources such as industry,agriculture and transportation.With the acceleration of industrialization and urbanization,the eco-environment of the city outskirts has become a hot spot of public concern.An analysis was conducted in this paper on the soil in the outskirts of Yixing City using frequency distribution functions.The heavy metal sources in this region had been divided into two components,i.e.natural background component and strong human disturbance component.The corresponding interpretation of the distribution pattern and features of heavy metal elements was presented by spatial analysis.The results showed that the strong human disturbance components of Hg,Pb,and Cu accounted for 36.9%, 26.7%,and 23.3%in their contents respectively,which indicated directly the serious effect of human activities on heavy metal contents.Hg and Pb,because of the human disturbance,showed the greatest spatial variability,and human activities intensified the heterogeneity of the spatial distribution.The anisotropic analysis showed the higher organisation of Hg and Zn in the direction of urban-rural transition,which indicated their spatial characteristics with urban-rural transition.Pb displayed distinctive structure in the vertical direction of urban-rural transition,which was largely controlled by highway distribution.Cu content in paddy fields was significantly higher than those of other land-use-types,and the agricultural non-point source pollution played an important role in the distribution pattern of Cu.

An Electrochemically Assisted Mechanically Controllable Break Junction Approach for Single Molecule Junction Conductance Measurements

我们向调查单个分子传导力汇报一条电气化学地帮助的机械地可控制的裂缝连接(EC-MCBJ ) 途径。与金 nanobridge 连接的电极对被电气化学的免职制作然后在一个 homebuilt MCBJ 平台上增长了。很多 Au- molecule-Au 连接被金 nanobridge 碎重复并且重新连接顺序生产。以便测量他们的单个分子传导力，统计传导力直方图为 benzene-1,4-dithiol (BDT ) 和 4,4-bipyridine (BPY ) 被产生。从这些直方图提取的价值被发现在象以前在文学报导的价值的一样的范围。我们的方法从过去常然而，获得这些以前报导的文学价值的是不同的因为它更快，更简单，更划算，并且改变电极材料是更方便的。

Development of a new ferulic acid certified reference material for use in clinical chemistry and pharmaceutical analysis

This study compares the results of three certified methods,namely differential scanning calorimetry(DSC),the mass balance(MB) method and coulometric titrimetry(CT),in the purity assessment of ferulic acid certified reference material(CRM).Purity and expanded uncertainty as determined by the three methods were respectively 99.81%,0.16%;99.79%,0.16%;and 99.81%,0.26%with,in all cases,a coverage factor(k) of 2(P ? 95%).The purity results are consistent indicating that the combination of DSC,the MB method and CT provides a confident assessment of the purity of suitable CRMs like ferulic acid.

具有高外量子效率和宽光谱(300～1000 nm)响应的有机-无机杂化锡基钙钛矿光电探测器（英文）

有机-无机杂化钙钛矿材料具有载流子迁移率高、扩散长度长、暗电流密度低、吸收边缘锋利等优点,因而成为用于光电探测的理想材料.但是,相对较小的带隙(1.6 eV)限制了这些材料在近红外区的光子捕获效率.本研究中,我们利用碘甲胺和铅-锡二元钙钛矿作为探测器的光吸收层,导电聚合物和富勒烯作为空穴和电子传输层,铟锡氧化物和铝作为阳极和阴极制备了光电探测器件.实验结果表明,当锡的含量达到30%时,探测器的光谱响应拓宽到1000 nm.此外,我们制备的探测器的光谱响应度达到0.39 A W^(-1),归一化探测率达到7×10^(12)Jones.器件的外量子效率在350到900 nm范围内,均超过50%,在550 nm处取得最大值,超过80%.

Study on four polymorphs of bifendate based on X-ray crystallography

Bifendate, a synthetic anti-hepatitis drug, exhibits polycrystalline mode phenomena with 2polymorphs reported(forms A and B). Single crystals of the known crystalline form B and 3 new crystallosolvates involving bifendate solvated with tetrahydrofuran(C), dioxane(D), and pyridine(E) in a stoichiometric ratio of 1:1 were obtained and characterized by X-ray crystallography, thermal analysis,and Fourier transform infrared(FT-IR) spectroscopy. The differences in molecular conformation,intermolecular interaction and crystal packing arrangement for the four polymorphs were determined and the basis for the polymorphisms was investigated. The rotation of single bonds resulted in different orientations for the biphenyl, methyl ester and methoxyl groups. All guest solvent molecules interacted with the host molecule via an interesting intercalative mode along the [1 0 0] direction in the channel formed by the host molecules through weak aromatic stacking interactions or non-classical hydrogen bonds, of which the volume and planarity played an important role in the intercalation of the host with the guest. The incorporation of solvent-augmented rotation of the C–C bond of the biphenyl group had a striking effect on the host molecular conformation and contributed to the formation of bifendate polymorphs. Moreover, the simulated powder X-ray diffraction(PXRD) patterns for each form were calculated on the basis of the single-crystal data and proved to be unique. The single-crystal structures of the four crystalline forms are reported in this paper.

Generation/collection mode of SECM with combined probe

这里，我们报导扫描电气化学的显微镜学， theta micropipette 在被采用支持薄中央玻璃墙分开的二个邻近的 water/1,2-dichloroethane 接口的一个新奇产生 / 收集操作模式：一个人充当发电机当时其它作为收集者。当尖端来临了到 insulate 底层时，产生水流，收集水流和收集效率显著地被提高。

Structural landscape on a series of rhein:Berberine cocrystal salt solvates:The formation,dissolution elucidation from experimental and theoretical investigations

The specific crystalline form of a compound remarkably affects its physicochemical properties.Therefore,a detailed analysis of the structural features and intermolecular interactions of a multi-component crystal is feasible to understand the relationships among the structure,physicochemical properties and the formation mechanism.In the present study,three novel cocrystal salt solvates of rhein and berberine were reported for the first time.Various solid characterizations and theoretical computations based on density functional theory(DFT)were carried out to demonstrate the intermolecular interactions.The theoretical computation shows that the strongest interaction existed between berberine cation and rhein anion,and the electrostatic interaction play a dominant role.However,no salt bond was observed between them.Further intrinsic dissolution rate analysis in water shows that the monohydrate exhibits 17 times enhancement in comparison with rhein.The rhein and berberine combined in ionic state in cocrystal salt is the main reason for the solubility improvement.This paper suggests that the interactions between the different components can be visualized and qualitatively and quantitatively analyzed by theoretical computation,which is helpful to understand the relationship between stereochemical structure and physicochemical properties of multi-component complex.

Improved transient electroluminescence technique based on time-correlated single-photon counting technology to evaluate organic mobility

The transient electroluminescence(EL)technique is widely used to evaluate the carrier mobility in the field of organic light emitting diodes.The traditional analog detection strategy using oscilloscopes is generally limited since the background noise causes an underestimation of the mobility value.In this paper,we utilize time-correlated single-photon counting(TCSPC)to probe the transient EL for mobility calculation.The measurements on tris(8-hydroxyquinoline)aluminum(Alq3)show that the electron mobilities obtained using the TCSPC technique are slightly higher than those obtained from the analog method at all the investigated voltages.Moreover,the TCSPC mobilities demonstrate weaker dependence on the root of electrical field compared to the oscilloscope mobilities.These improvements are attributed to the unique principle of TCSPC,which quantifies the EL intensity by counting the number of single-photon pulses,improving its single-photon sensitivity and elimi-nating the negative impacts of electrical noise.These advantages make TCSPC a powerful technique in the characterization of time-resolved electroluminescence.