同步辐射显微CT研究药物制剂结构的进展

固体药物制剂的结构研究是实现优化给药的基础,也是给药系统创新的重要内容。同步辐射显微CT(synchrotron radiation X-ray microtomography,SR-μCT)技术,不仅能够在微米、亚微米级分辨率上展示药剂粉体、微粒给药系统、片剂类固体剂型等三维静态形貌特征,而且能够连续观察缓控释制剂释药过程中的动态变化,揭示释药速率的关键结构因素,为新型给药系统的设计、质量控制提供依据和新方法。综述了同步辐射显微CT在药物制剂结构研究方面的国内外进展。我国新近应用该技术开展了药剂粉体颗粒的表征、制剂微观结构及基于结构的释放动力学研究,在药物的晶型研究、颗粒混合及分层的评价、制剂复杂结构的分形特征、难溶性药物凝胶骨架片的水化动力学和渗透泵三维立体释放动力学研究方面取得了一系列进展。

高分辨三维X射线显微成像在药物制剂结构分析中的应用

药物制剂的结构研究能够帮助更加全面地评价药物制剂的质量,也有助于新型药物制剂的设计和创新。高分辨三维X射线显微成像技术能够在微米级甚至纳米级空间分辨率上原位、无损地展示粉末、颗粒、片剂、胶囊等固体制剂的三维结构信息,为新型制剂的创新和质量控制提供新方法。本文在介绍高分辨三维X射线显微成像技术的原理、发展及其研究药物制剂结构的基本流程的基础上,综述了其在药物制剂结构研究方面的国内外进展,为相关研究提供参考。

绘图实践提升药剂学课程教学效果的探索

如何在有限的学习时间内帮助学生认识和理解众多药物制剂的结构、制备流程和作用原理,掌握药物制剂的基本特征,为从事制剂研发、生产和药事服务奠定基础,是药剂学课程教学改革必须解决的问题。以药物制剂作为绘图对象并进行解析,探索药剂学绘图实践的方法和效果,为医药院校专业课程建设提供参考。

Recent developments in the physical structure of solid formulations:a comprehensive review

Solid formulations represent the most widely used dosage forms,and their structural attributes significantly impact the efficacy of drugs.Consequently,delving into the study of solid formulation structures is of paramount importance.This paper employs bibliometrics to summarize references on solid formulations and physical structure over the past 5 years,providing a visual representation through CiteSpace.Additionally,we explore influential factors affecting the structure of solid formulations at three distinct levels:raw material,intermediate,and final product.It delves into the discussion of various characterization techniques employed to analyze the physical structure of solid formulations.The techniques include scanning electron microscopy,transmission electron microscopy,X-ray diffraction,nuclear magnetic resonance,LF-nuclear magnetic resonance,thermal analysis,and terahertz.Emphasis is placed on the significance of investigating formulation structures,serving as a found ational step for future research and development in this field.This comprehensive approach aims to contribute to the understanding and advancement of solid formulations for enhanced drug effectiveness.

从结构出发的制剂一致性研究策略

制剂一致性研究中如何提高效率、充分保障仿制制剂与原研药一致,亟待发展新的技术和方法。对于具有结构特征的固体制剂、微粒分散体系,结构是其特定处方与工艺技术的结果,决定其递送药物的释放行为及其体内药代动力学行为。传统表征技术不能对结构进行定量,而同步辐射成像等新一代结构定量表征技术,在揭示制剂内部结构方面展现了前所未有的能力,能定量表征制剂的静态结构和动态结构,实现制剂工艺的逆向工程剖析和制剂间结构异同的甄别。本团队建立了方法学,采用该技术实现了在静态结构(原辅料粉体结构、颗粒单元结构、片剂结构和膜结构等)和水化等动态结构、固体制剂工艺甄别等方面的应用,将制剂的结构划分为从剂型到制剂中间体、动态结构、分子结构等四级结构,提出了基于制剂结构的药物一致性评价新策略。在制剂释药行为一致的基础上,制剂内部精细结构的一致更有助于确保制剂的一致性。

基于高生物利用度的创新组分结构中药制剂技术研究

中药制剂现代化是目前中药发展进程中的主要方向,而中药是一个具有多组分、多途径、多靶点整体作用特点的复杂体系,存在着物质基础尚不明确、作用机制不清晰等问题,这些都制约着中药制剂现代化的发展。加强中药组分的理论探索,提高组分制剂技术水平,促进中药组分制剂的发展,对实现中药现代化具有重要的意义。以"组分结构"理论为指导,从原材料前处理工艺和制剂成型技术2个方面系统阐述,以提出高组分生物利用度为目的,论述创新组分结构中药制剂的研究思路。

Research progress of Ag_3PO_4-based photocatalyst: Fundamentals and performance enhancement

Ag3PO4 is found to be a highly efficient photocatalyst and receives great attention. The high activity of the photocatalyst is credited to the intrinsic electronic structure. The morphology control and nano-composite fabrication are used to improve the performance and practicability. This paper reviews the structure, properties and some theoretical aspects of Ag3PO4 single crystal. Also, the major strategies, namely the morphology control and hetero-nanostructure construction, as ways to improve the performance of Ag3PO4-based photocatalysts, are summarized with the aid of some typical instances.

Preparation and Characterization of Pt-Sn/SBA-15 Catalysts and Their Catalytic Performances for Long Chain Alkane Dehydrogenation

A series of the Pt-Sn/SBA-15 catalysts were prepared and their properties characterized by using X-ray powder diffraction （XRD）, N2 adsorption-desorption, high resolution transmission electron microscope, X-ray photoelectron spectroscopy （XPS） and H2-temperature programmed reduction. Their performances in long chain alkane dehydrogenation were evaluated in a fixed-bed microreactor with dodecane as a model alkane. The results indicated that SBA-15 maintained the well-order mesoporous structure during the reaction. The performance of the catalyst was found not dominated by its textural properties, but by the molar ratio of Sn to Pt which governed the degree of Sn reduction. Owing to the highest degree of Sn reduction, 1% （by mass） Pt-1.8% （by mass） Sn/SBA-15 showed the best catalytic activity. At 0.1 MPa and 470℃, the molar ratio of hydrogen to alkane at 4, and liquid hourly space velocity （LHSV） 20 h^-1, the dodecane conversion is 10%, and the dodecene selectivity is about 70%.

Crystal Structure of Ethoxyethyl 3-(2-Chloro-5-pyridyl methylamino)-2-cyano-4-methylpent-2-enoate

The crystal of the title compound C17H22ClN3O3(Mr = 351.83) was prepared and its structure was determined by X-ray single-crystal diffraction. The crystal belongs to monoclinic, space group P21/n with the following crystallographic parameters: a = 14.7641(1), b = 9.0050(7), c = 15.4874(1) ? =116.9590(1)? V = 1835.3(3) ?, Z = 4, Dx = 1.273 g/cm3, (MoK? = 0.227mm-1, F(000) = 744, the final R = 0.0516 and wR = 0.1594 for 2168 observed reflections. The X-ray data confirmed the z-sterochemistry of active cyanoacrylates and the presence of a planar core stablized by an intramolecular hydrogen bond between the ester carbonyl oxygen and the pyridyl methylamino hydrogen atom.

Molecular structures and activity of organic depressants for marmatite,jamesonite and pyrite flotation

Ten kinds of organic depressants were used to investigate the depressing performance on marmatite and pyrite.Flotation results show that the organic compounds only with single group of hydroxyl(-OH),carboxyl(-COOH) or amino(-NH2) in molecule are ineffective in depressing marmatite,jamesonite and pyrite.The combinations of these functional groups still cannot enhance the depressing ability of organic depressant.The thioglycollic acid containing reductive functional group(-SH) has a good depressing performance for marmatite and pyrite.The presence of benzene ring in molecule can enhance the depressing performance.The functional group electronegativity,hydrophilic-hydrophobic indexes and frontier orbital of organic depressants were calculated,and the criterion for the depressing effect of organic depressants to sulphide minerals was proposed.

Fabrication of curved micro structures on photoresist layer

A novel fabrication process for micro patterns with curvature was introduced. The curved structures were made by compensating rectangular micro structures with liquid photoresist layer. Because of the surface tension of the liquid in micro scale, various shapes of meniscus can he made on the micro channels. The micro channels were made on the silicon suhstrate in advance, and then the liquid layer was coated on the micro channels. From the nature of liquid behavior, the curved patterns with smooth surface are obtained, which cannot be made easily with the conventional mechanical machining, as well as with the microfabrication processes, such as wet and dry etching. With this principle, it is expected that the smooth and curved surfaces can be made by simple processes and the results can be applied widely, such as optical patterns.

Advances in the management of acquired resistance to EGFR-TKI in non-small cell lung cancer

Drugs that specifically target the tyrosine kinase domain of epidermal growth factor receptor(EGFR), such as erlotinib or gefitinib, have exhibited striking efficacy in non-small cell lung cancer(NSCLC) patients harboring activating EGFR mutations. However, acquired resistance inevitably develops and remains a serious barrier for the successful management of patients with this disease. Multiple mechanisms are reportedly involved in the process of acquired resistance, which provide new insights into the management of EGFRtyrosine kinase inhibitor(EGFR-TKI) resistance. Here, we provide an overview of the emerging treatment approaches for patients with EGFR-TKI resistance.

Design of the Metal Precursors Molecular Structures in Impregnating Solutions for Preparation of Efficient Ni Mo/Al_2O_3 Hydrodesulfurization Catalysts

The molecular structures of metal precursors in the impregnating solution were designed so as to prepare efficient Ni Mo/Al_2O_3 hydrodesulfurization(HDS) catalysts. At first, five typical impregnating solutions were designed; the existing metal precursors, such as [Mo4(citrate)2O11]^(4-)-like, [P2Mo18O62]^(6-)-like and [P2Mo5O23]^(6-)-like species in the solutions were confirmed by laser Raman spectroscopy(LRS). The UV-Vis spectra results indicated that the solutions containing both phosphoric acid and citric acid could change the existing form of nickel species. Five corresponding Ni Mo/Al_2O_3 catalysts were prepared by the incipient wetness impregnation method. The LRS analysis results of dried catalysts showed that the above metal precursors could be partly retained on alumina support after impregnation and drying, although the interface reaction between different metal precursors and alumina support unavoidably took place. Then the catalysts were sulfided and characterized by N2 physisorption, TEM and XPS analyses. The results showed that different metal precursors in impregnating solution could mainly result in the difference in both the morphology of(Ni)Mo S2 slabs and the promoting effect of Ni species. The catalyst prepared mainly with [P2Mo5O23]^(6-)-like species used as precursors exhibited worse dispersion of(Ni)Mo S2 slabs and lower ratio of Ni–Mo–S active phases than the one with [Mo4(citrate)2O11]^(4-)-like species. Promisingly, the catalyst prepared with co-existing [Mo4(citrate)2O11]^(4-)-like, [P2Mo18O62]^(6-)-like and [P2Mo5O23]^(6-)-like species showed better hydrodesulfurization activity for 4,6-DMDBT thanks to its more well-dispersed Ni–Mo–S active phases.

Effects of Low Concentration Methanol, PVP and PVCap on Structure-I Methane Hydrate Formation

Kinetic mechanisms describing how THIs （thermodynamic hydrate inhibitors） and KHIs （kinetic hydrate inhibitors） work on gas hydrate formation have drawn interests for decades. These mechanisms could be better revealed with more fundamental experimental studies. With experiments performed in an isochoric cell with continuous cooling and stirring, this paper presents observed effects of methanol, PVP （polyvinylpyrrolidone, Mw= 15,000） and PVCap （polyvinylcaprolactam, Mw = 6,000） on both nucleation and growth of structure-I methane hydrate at concentrations 100 to 3,000 ppm （i.e., 0.01 to 0.3 wt%）. The results suggest that methanol had no significant effect on nucleation, while it weakly promoted, spontaneous hydrate growth at an early stage. PVP and PVCap gave reduced average nucleation rate at and prior to hydrate onset, while increased the induction time and the degree of sub-cooling. PVP gave no observable effect on total gas intake and average hydrate growth rate. A decreased total gas intake was observed for all concentrations of PVCap.

Porous Structure, Salt Component Distribution and Catalytic Preference of Zinc Acetate Catalysts for Vinylacetate Synthesis on Modified Carbon Supports

The main problem in an efficient Zn（CH3COO）2/AC （AC-activated carbon） catalyst preparation is the achievement of uniform distribution of highly dispersed salt component on the activated carbon （AC） surface. The solution of this problem is modification of the AC by hydrogen peroxide （H202） oxidation of the surface and treatment of AC with acetic acid as well as special methods of salt deposition and catalyst drying. The investigations of these ways of AC surface modification （treatment of AC with acetic acid and H2O2） have demonstrated the obtained AC to have both an increased adsorption capacity as to Zn（OAc）2 and optimum volumes of meso- and micro-pores as well as high catalyst activity in vinyl acetate （VA） synthesis. The characteristics of supports and catalysts were found out by benzene, water and acetic acid vapors adsorption. The distribution of the salt on the AC surface was studied by small-angle X-ray scattering （SAXS）, by scanning electron microscopy （SEM） and X-ray micro-analysis （XMA）. The catalysts were tested in vinyl acetate synthesis in flow-bed isothermal reactor by cyclic method at 175, 205 and 230℃.

Effects of transgenic poplar clone 741 with insect resistance on structure and diversity of arthropod community

Arthropod community structure and diversity were investigated in transgenic insect-resistant hybrid poplar 741 field trial plots, which had five isogenic clones with two genes （Bt. toxin [Cry IAc] and arrowhead proteinase inhibitor [API]） in comparison to control plots. Transgenic poplar clones were investigated according to their insect resistance （high and medium resistant clones）, being systematically probed into varying levels with feeding tests before. Investigations were carded out during three years （2002, 2003 and 2005）. The results indicated that among the basal species, transgenic plants in general had lower amounts of phytophagous insects, and an increased quantity of neutral arthropods such as saprophytic and strolling species. Among the top and intermediate species in transgenic variants, the quantity of predatory natural enemies was increased, while the amount of parasitoid ones was slightly reduced. The arthropod community characteristic indices were analyzed from different aspects in the three variants. It was discovered that, not only the characteristic indices of the whole arthropod community, but also the characteristic indices of the sub-communities （such as natural enemy, pest and neutral arthropods） and the functional groups categorized by their feeding patterns, showed a higher diversity and evenness and a lower dominancy concentration indices in the high-resistant and medium-resistant plots compared with the control. Transgenic poplar 741 showed improved ecological effects both in partial and total aspects. It could be concluded that composition and structure of the arthropod community in plots with transgenic insect-resistant poplar were turned to be more reasonable and itsdiversity and stability was enhanced.

Sirtuin 5:a review of structure,known inhibitors and clues for developing new inhibitors

Sirtuins(SIRTs) are nicotinamide adenine dinucleotide(NAD^+)-dependent protein deacetylases,which regulate important biological processes ranging from apoptosis,age-associated pathophysiologies,adipocyte and muscle differentiation,and energy expenditure to gluconeogenesis.Very recently,sirtuin 5(SIRT5) has received considerable attention due to that it was found to have weak deacetylase activity but strong desuccinylase,demalonylase and deglutarylase activities,and it was also found to be associated with several human diseases such as cancer,Alzheimer's disease,and Parkinson's disease.In this review,we for the first time summarized the structure characteristics,known peptide and small-molecule inhibitors of SIRT5,extracted some clues from current available information and introduced some feasible,practical in silico methods,which might be useful in further efforts to develop new SIRT5 inhibitors.

Fabrication of rod-shaped β-FeOOH: the roles of polyethylene glycol and chlorine anion

β-FeOOH nanorods of 40 nm wide and 450 nm long were fabricated through precisely regulating the hydrolysis kinetics of Fe3＋ in polyethylene glycol and the concentration of C1- as the structure-directing agent. Detailed structural and chemical analyses of the intermediates during the synthesis identified that the strong interaction between PEG and Fe3＋ modulated the hydrolysis kinetics of Fe3＋and prevented the aggregation of β-FeOOH nanorods; while C1- provided sufficient nucleation sites, stabilized the hollow channel of β-FeOOH, and more importantly induced the growth of the nanorods along [001] direction.

Diversity evolution and jump of Polo-like kinase 1 inhibitors

Polo-like kinase 1 （Plkl）, a member of a family of serine/threonine kinases, is an attractive target for the development of anti- cancer drugs because it is involved in the regulation of cell-cycle progression and cytokinesis. This kinase provides two pock- ets for developing Plkl inhibitors： the N-terminal catalytic domain （NCD） and the polo-box domain （PBD）. For both of the two pockets, some natural products were identified as Plkl inhibitors and some synthetic Plkl inhibitors were developed by mimicking ATP and phosphopeptides, natural products binding to NCD and PBD respectively. This article not only reviews the progression of Plkl inhibitors binding to these two pockets, but also discusses diversity evolution and jump in the process of drug development using Plkl inhibitors as examples and how they impact on drug design and pharmacopbore modeling.

Structure-based design of hexahydropyrimidin-5-ols as novel non-peptidic β-secretase inhibitors

Based upon the crystal structure of a previously reported fragment hit that binds to Corresponding author. β-secretase, a novel series of non-peptidic small-molecule β-secretase inhibitors, namely hexahydropyrimidin-5-ols, along with two series of their analogues, were rationally designed through structural modification. The CADD study was performed and revealed good expectation. Inhibitory activities of the corresponding structural cores were tested, which provided further support for our design approach.