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Investigation of physicochemical properties and in-vitro in-vivo evaluation of agomelatine polymorphs

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Asian Journal of Pharmaceutical Sciences 2013年第3期8卷 181-190页

作者： Wei Du Yuefang Zhou Yafei Gong Chunshun Zhao Sun Yat-sen University Guangzhou 510006China

In the present study,Form I,Form II and Form III of agomelatine were prepared to investigate the variability of polymorphs,then the in-vitro in-vivo correlation were *** presence of three polymorphs of agomelatine was corroborated through studies by XRPD,TGA and *** the forms obtained were then subjected to the powder and intrinsic dissolution *** IDR ranked in the order of Form III>Form I>Form *** I and Form III both underwent solvent-mediated phase transformation(SMPT)to Form II during dissolution and the transition points were 62 and 45 min,*** profiles were acquired after oral administration of tablets,showing that the ka and AUC0e12 h of Form I,Form II,Form III were 0.580.11,0.340.05,0.740.07 h1 and 296.2549.39,186.0545.93,331.1654.74 ng*h/ml,*** linearities between IDR and ka,IDR and AUC were established,suggesting that the agomelatine polymorphic forms with faster dissolution rates in-vitro would increase the rate and extent of oral absorption *** results demonstrated that IDR was predictive in estimating the relative bioavailability of agomelatine polymorphic forms.

关键词： Agomelatine polymorphs Intrinsic dissolution rate Pharmacokinetics IVIVC

Interface engineering for boosting electrocatalytic performance of CoP-Co_(2)P polymorphs for all-pH hydrogen evolution reaction and alkaline overall water splitting

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Science China Materials 2022年第9期65卷 2433-2444页

作者： Lei Chen Jin-Tao Ren Zhong-Yong Yuan Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) National Institute for Advanced MaterialsSchool of Materials Science and EngineeringNankai UniversityTianjin 300350China

Exploring cobalt phosphide catalysts with abundant active sites and outstanding intrinsic activity for active and robust hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)is highly ***,by the fine-tuning thermal-reduction treatment of cobalt phosphonates with spherical shape,the novel carbon-wrapped CoP-Co_(2)P polymorphs are rationally *** unique hierarchical porous architecture and heterointerface of CoP-Co_(2)P not only increase active sites but also ensure intrinsic *** resultant catalyst exhibits significantly boosted HER activity in a wide pH range,for instance,a current density of 10 mA cm^(-2) at the overpotential of 81 mV in 0.5 mol L^(-1) H_(2)SO_(4),109 mV in 1.0 mol L^(-1) KOH,and 227 mV in 1.0 mol L^(-1) phosphate buffer saline,and remarkable OER activity(1.53 V@10 mA cm^(-2) in 1.0 mol L^(-1) KOH),associated with the impressive stability for each ***,serving as the bifunctional electrocatalysts in a two-electrode electrolyzer for overall water splitting,a low cell voltage of 1.60 V can deliver a current density of 10 mA cm^(-2) in 1.0 mol L^(-1) *** structural evolution process of the CoP-Co_(2)P catalyst during electrolysis is thoroughly *** work presents a new approach for designing and fabricating efficient and affordable metal phosphides for various electrochemical technologies.

关键词： cobalt phosphides polymorphs heterointerface hydrogen evolution oxygen evolution

Syntheses, characterization, and theoretical calculation of Rb2Mg3（P2O7）2 polymorphs with deep-ultraviolet cutoff edges

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Science China Materials 2020年第4期63卷 593-601页

作者： Hongping Wu Shiwei Liu Shichao Cheng Hongwei Yu Zhanggui Hu Jiyang Wang Yicheng Wu Tianjin Key Laboratory of Functional Crystal Materials Institute of Functional CrystalTianjin University of TechnologyTianjin 300384China Xinjiang Technical Institute of Physics&Chemistry Chinese Academy of SciencesUrumqi 830011China

By the combination of the isolated P2O7 dimers and Mg O4 tetrahedra,α-andβ-Rb2Mg3(P2O7)2 polymorphs were synthesized by a high-temperature solution method.α-Rb2Mg3(P2O7)2 crystallizes in non-centrosymmetric space group P212121,whileβ-Rb2Mg3(P2O7)2 crystallizes in centrosymmetric P21/*** structures contain a three dimensional[Mg3P4O14]^2- anionic framework,while Rb^+ cations are in the *** analyses show that the isolated P2O7 dimers can easily adjust their variable configurations and orientations to fit the different coordination environments of the cations,which is conducive to the formation of *** phase transformation process fromα-toβ-Rb2Mg3(P2O7)2 was further investigated by powder X-ray diffraction and thermal gravimetric/differential scanning calorimetry *** addition,UV-vis-NIR diffusion spectra indicate both materials have deep-ultraviolet cut-off edges(below 190 nm).α-Rb2Mg3(P2O7)2 is second-harmonic generation(SHG)-active and the origin of SHG response was investigated by the SHG density *** first-principle calculations were also carried out to illuminate their structure-property relationships.

关键词： polymorphs phosphate deep-ultraviolet transparent window structure-property relationship

Formation of Calcium Carbonate polymorphs Induced by Living Microalgae

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Journal of Biomaterials and Nanobiotechnology 2012年第4期3卷 413-420页

作者： Giulia Santomauro Johannes Baier Wanjing Huang Stefan Pezold Joachim Bill Institute for Materials Science University of Stuttgart Stuttgart Germany

Calcium carbonate (CaCO3) occurs in the three polymorphs calcite, aragonite and vaterite. The formation of these crystals in inorganic solutions is influenced by parameters like pH, temperature or impurities. Living freshwater microalgae can also induce the formation of CaCO3 when they live in a suitable environment containing saturated amounts of Ca2+. Through this biologically induced biomineralization only the formation of the polymorph calcite has been reported yet. We investigated the precipitates which have been formed in solutions containing the freshwater microalgae Scenedesmus obliquus and different zinc amounts (0, 3.27 and 6.53 mg Zn2+/l) by XRD and SEM. As references precipitates from the same solutions but without algae were investigated. We could show that the presence of living microalgae has a great influence on the precipitation of calcium carbonate crystals. In algae-containing media without or with a low zinc amount always calcite and aragonite are formed. In the corresponding medium with 6.53 mg Zn2+/l pure aragonite crystals were built. In contrast, in the inorganic, algae-free solutions without zinc, pure calcite is precipitated. Both inorganic solutions with zinc show major calcite precipitation and weak aragonite precipitation. Thus the algae cells advance significantly the formation of aragonite, which is enhanced by the presence of zinc cations in the media. Possible mechanisms are discussed.

关键词： CaCO3 polymorphs Biomineralization Zinc Microalgae XRD

Nanomics of Nanoselenium in Cancer Cells: Mitochondria-Mediated Protein Regulation Mechanism of polymorphs-Dependent Inhibition of Nanoselenium on Cancer Cells

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Nanomics of Nanoselenium in Cancer Cells: Mitochondria-Media...

Physical properties of B_4N_4-Ⅰ and B_4N_4-Ⅱ:First-principles study

河南省化学会2016年学术年会

作者： Ge Wang Yuming Guo Gai Yang Lin Yang Xiaoming Ma Kui Wang Lin Zhu Jiaojiao Sun Xiaobing Wang Hua Zhang Collaborative Innovation Center of Henan Province for Green Manufacturing of Fine Chemicals Key Laboratory of Green Chemical Media and Reactions Ministry of Education School of Chemistry and Chemical Engineering Henan Normal University

The present study was(i) to prepare two types of selenium nanoparticles, namely an amorphous form of selenium quantum dots(A-Se QDs) and a crystalline form of selenium quantum dots(C-Se QDs);and(ii) to investigate the nano-bio interactions of A-Se QDs and C-Se QDs in MCF-7, Hep G2, He La, NIH/3T3, L929 cells and BRL-3A cells. It was found that A-Se QDs could induce the mitochondria-mediated apoptosis,necrosis and death of cells, while C-Se QDs had much weaker effects. This polymorphs-dependent anti-proliferative activity of nano-selenium was scarcely reported..Further investigation demonstrated that A-Se QDs could differentially regulate 61 proteins and several pathways related to stress response, protein synthesis, cell migration and cell cycle, including "p38 MAPK Signaling", "p53 Signaling", "14-3-3-mediated Signaling", "p70S6K Signaling" and "Protein Ubiquitination Pathway". This was the first report to demonstrate the involvement of protein synthesis and post-translational modification pathways in the anti-proliferative activity associated with NMs. Compared with previously fragmentary studies, this study use a nanomics approach combining bioinformatics and proteomics to systematically investigate the nano-bio interactions of selenium nanoparticles in cancer cells.

关键词： nanoselenium polymorphs nano-bio interactions bioinformatics nanomics

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Chinese Physics B 2019年第3期28卷 283-290页

作者： Zhenyang Ma Peng Wang Fang Yan Chunlei Shi Yi Tian Key Laboratory of Civil Aircraft Airworthiness Technology Civil Aircraft Airworthiness and Repair Key Laboratory of TianjinSchool of AirworthinessCivil Aviation University of China

The structural, mechanical, electronic, mechanical anisotropy, and thermal properties of boron nitride(BN) polymorphs, such as B_4 N-4-Ⅰ and B4 N4-Ⅱ, are investigated under ambient pressure utilizing first-principles generalized gradient approximation calculations using an ultrasoft pseudopotential scheme. The phonon spectra and elastic constants reveal that B_4 N_4-Ⅰ is dynamically and mechanically stable at the pressure of 0 GPa and temperature of 0 K. Anisotropic calculations indicate that both B_4 N_4-Ⅰ and B4 N4-Ⅱ exhibit higher anisotropy of Young's modulus than cubic BN(c-BN). B_4 N_4-Ⅱ and B_4 N_4-Ⅰ present indirect and wide band gaps of 5.32 eV and 4.86 eV, respectively. In addition, B_4 N_4-Ⅰ is more brittle than B_4 N_4-Ⅱ. Moreover, the minimum thermal conductivity,κmin, of B4 N4-Ⅱ at 300 K is 1.92 W/(cm·K), which is slightly higher than those of B_4 N_4-Ⅰ and c-BN(1.84 W/(cm-K) and 1.83 W/(cm-K), respectively. However, κ_(min) of B_4 N_4-Ⅰ is slightly higher than that of c-BN.

关键词： BN polymorphs mechanical properties electronic properties mechanical anisotropic properties

Texture Induced by Molecular Weight Dispersity: Polymorphism within Poly(L-lactic acid) Spherulites

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Chinese Journal of Polymer Science 2020年第12期38卷 1365-1373页

作者： Da-Peng Hu Min Chen Yu-Hui Yang Han-Ying Li Ministry of Education Key Laboratory of Macromolecular Synthesis and Funtinalizatin Department of Polymer Science and EngineeringZhejing UniversityHangzhou 310027 China

Poly(L-lactic acid)(PLLA)has drawn much attention due to its excellent medical and pharmaceutical applications for *** a semi-crystalline polymer,morphology and crystal structure of PLLA greatly determine its ***,w e demonstrate,for PLLA films,a nonconventional texture featuring two types of spherulites emerging in pairs to form a distinct nested structure where a small spherulite(〜10μm)is embedded in a large one(100μm to 300μm).In addition to the size,the molecular weight and polymorph are different in the large and small *** a-form and relatively low molecular weight are identified in the large spherulites,while meta-stable a'-form and relatively high molecular weight in the small *** differences suggest that the polydisperse PLLA polymers fractionate during film formation and the high-molecular-weight fraction crystallizes into the small spherulites with meta-stable structure because of its complicated polymer entanglement and high *** contrast,the rest of polymers crystallize into the large spherulites with the thermodynamically stable ***,this texture exhibits accelerated PLLA degradation initiated from the small spherulites,which is distinct from the typical PLLA *** provided by this work may lead to new texture-properties relationship associated with polydispersity of molecular weight.

关键词： PLLA Spherulite polymorphs Molecular weight

Manipulation of successive crystalline transformations to control electron transfer and switchable functions

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National Science Review 2018年第4期5卷 507-515页

作者： Cheng-Qi Jiao Wen-Jing Jiang Yin-Shan Meng Wen Wen Liang Zhao Jun-Li Wang Ji-Xiang Hu Gagik G.Gurzadyan Chun-Ying Duan Tao Liu State Key Laboratory of Fine Chemicals Dalian University of Technology Institute of Artificial Photosynthesis State Key Laboratory of Fine Chemicals Dalian University of Technology

Electron transfer in solid is crucial to switchable magnetic,electrical,optical and mechanical ***,it is a formidable challenge to control electron-transfer behaviors via manipulation of crystalline phases,especially through dynamic crystalline ***,three crystalline phases of an{Fe2Co2}compound were obtained via enhancement of intermolecularπ···πinteractions inducingsuccessive single-crystal-to-single-crystal transformations,from solvated 1·2CH3OH·4H2O,to desolvated1 and its polymorph 1a accompanying electron transfer.1·2CH3OH·4H2O showed thermally inducedreversible intermetallic electron transfer in mother *** electron-transfer behavior was observed in 1.1a showed reversible intermetallic electron transfer upon thermal treatment or alternative irradiation with808-and 532-nm lasers at cryogenic *** electron-transfer behaviors significantly change the magnetic and optical properties,providing a strategy to realize different electron-transfer behaviors andswitchable functions viaπ···πinteractions manipulated dynamic crystalline transformation.

关键词： electron-transfer dynamic structural transformation successive crystalline transformations reversible polymorphs

Physics, chemistry, and Hirshfeld surface analyses of gamma-irradiated thalidomide to evaluate behavior under sterilization doses

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Journal of Pharmaceutical Analysis 2018年第3期8卷 194-201页

作者： Valner A.F.S.N.Mussel Max R Ferreira Maria B.E Marques Maria I.Yoshida Mariana R.Almeida Bernardo L.Rodrigues Wagner N.Mussel Departamento de Quimica ICExUniversidade Federal de Minas Gerais-UFMGAv.Antonio Carlos 662731270-901 Belo HorizonteMGBrazil CNEN-CDTN Comissao Nacional de Energia Nuclear-Centro de Desenvolvimento da Tecnologia NuclearAv.Antonio Carlos6627 Belo HorizonteMGBrazil

Thalidomide was indicated as a sedative and antiemetic and prescribed for pregnant women. Its tragic teratogenic effects culminated in withdrawal from the market. Since the discovery of its anti-angiogenic and anti-inflammatory actions, thalidomide has been used in the treatment of leprosy and multiple myeloma, which justify studies of its stability. We investigated the effects of irradiation of thalidomide up to 100 kGy （fourfold the usual sterilizing dose for pharmaceutics）. The polymorph of thalidomide was obtained in an isothermal experiment at 270℃. All samples underwent gamma irradiation for specific times. At different doses, decomposition of the pharmaceutical was not observed up to 100 kGy. The observed effect was angle turning between the phthalimide and glutarimide rings modulated by repulsion towards the carbonyl group, leading to a stable energetic configuration, as measured by the equilibrium in the torsion angle after irradiation. The thalidomide molecule has a center of symmetry, so a full turn starting from 57.3° will lead to an identical molecule. Further irradiation will start the process again. Samples irradiated at 30 and 100 kGy have more compact unit cells and a lower volume, which leads to an increase in the intermolecular hydrogen interaction within the unit cell, resulting in higher thermal stability for polymorph α.

关键词： Thalidomide Thermal stability polymorphs Gamma irradiation Hirshfeld