Supramolecular self-assembly based on directed hydrogen bonding

A series of hydrogen-bonding monomers has been constructed and shown to form discrete aggregates both in solution and in the solid state.     

胞元结构X-Ray三维成像及其FEM模拟

采用微纳米X-Ray断面成像技术,通过对含有CaCl2生物淀粉膨化结构材料三维成像规律的研究,确定了胞元体结构形态,并分析了断层胞元分布规律.建立了带有微细孔洞结构材料三维几何描述模型,通过理论建模和数字编程实现了与非线性有限元的连接,分析了微米级胞体材料受载后的场变量分布.     

Piper tectoniifolium Kunth: A New Natural Source of the Bioactive Neolignan (−)-Grandisin

The Piper species are a recognized botanical source of a broad structural diversity of lignans and its derivatives. For the first time, Piper tectoniifolium Kunth is presented as a promising natural source of the bioactive (−)-grandisin. Phytochemical analyses of extracts from its leaves, branches and inflorescences showed the presence of the target compound in large amounts, with leaf extracts found to contain up to 52.78% in its composition. A new HPLC-DAD-UV method was developed and validated to be selective for the identification of (−)-grandisin being sensitive, linear, precise, exact, robust and with a recovery above 90%. The absolute configuration of the molecule was determined by X-ray diffraction. Despite the identification of several enantiomers in plant extracts, the major isolated substance was characterized to be the (−)-grandisin enantiomer. In vascular reactivity tests, it was shown that the grandisin purified from botanical extracts presented an endothelium-dependent vasorelaxant effect with an IC₅₀ of 9.8 ± 1.22 μM and around 80% relaxation at 30 μM. These results suggest that P. tectoniifolium has the potential to serve as a renewable source of grandisin on a large scale and the potential to serve as template for development of new drugs for vascular diseases with emphasis on disorders related to endothelial disfunction.     

A Potentiometric and Spectroscopic Study on the Interaction Between Human Immunoglobulin G and Sodium Perfluorooctanoate in Aqueous Solution

The interaction between human immunoglobulin G (IgG) and sodium perfluorooctanate (SPFO) has been characterized by a combination of UV-vis and UV-CD spectroscopies and ion selective electrodes. The study determined that there were true specific unions between SPFO and IgG. The conformational changes at the bulk solution, induced by SPFO, were well characterized by UV-vis and UV-CD spectroscopies. Chemical and thermal unfolding were analysed and the thermodynamic parameters were determined.