A DNA biosensor with [Ru（DA-bpy）3]Cl2（DA-bpy：4,4＇-diamino-2,2＇-bipyridine） （RuL） as the electrochemical probe was prepared on pyrolytic graphite electrode （PGE） through the supramolecular interaction betwee...A DNA biosensor with [Ru（DA-bpy）3]Cl2（DA-bpy：4,4＇-diamino-2,2＇-bipyridine） （RuL） as the electrochemical probe was prepared on pyrolytic graphite electrode （PGE） through the supramolecular interaction between RuL complex and DNA template. Cyclic voltammetry of RuL-DNA film showed a pair of stable and reversible peaks corresponding to the Ru（Ⅲ）/Ru（Ⅲ） redox potential of-0.165 V versus AglAgCl in pa 7.4 0.1 mol·L^-1Tris-HCl. The electron transfer was expected across the double-strand DNA by an ＂electron tunneling＂ mechanism. When the DNA biosensor was immerged in gold （Ⅲ） buffer solution, the current peak signal （I） of the RuL-DNA supramolecular depressed and △I was linear in the concentration range of Au ion from 1×10^-7 to 2×10^-5 mol·L^-1 with a regression coefficient of 0.9879. The detection limit was 5×10^-8 mol·L^-1. The developed procedures were applied to the analysis of synthetic samples of real materials with good sensitivity and selectivity.展开更多
Four novel lanthanide-based coordination polymers, [Ln(PBDC)(HPBDC)(H2O)3] (H2PBDC=p-carboxylphenoxyacetate; Ln = La (1), Pr (2), Nd (3)) and [La2(PBDC)3(H2O)4] (4), have been prepared through hydrothermal synthetic m...Four novel lanthanide-based coordination polymers, [Ln(PBDC)(HPBDC)(H2O)3] (H2PBDC=p-carboxylphenoxyacetate; Ln = La (1), Pr (2), Nd (3)) and [La2(PBDC)3(H2O)4] (4), have been prepared through hydrothermal synthetic methods. Compounds 1―3 are isomorphous and exhibit one-dimensional (1D) chain-like motifs, while compound 4 features a complicated three-dimensional (3D) architecture, which is designed and synthesized based on the inspiration from the structure characterization of compound 1. Under the similar reaction conditions, the carboxyl in compound 1 may be further deprotonated by adding the organic base of 2,2'-bipyridine. This subtle change caused a significant difference in the structures, from 1D chain of 1 to a 3D structure of 4. In addition, IR, UV-Vis, TGA and magenetic properties are also investigated in this paper.展开更多
We report on a cross-sectional high resolution transmission electron microscope study of lead sulfide nanocrystal quantum dots （NCQDs） dispersed on electron-transparent silicon nanopillars that enables nearly atomic...We report on a cross-sectional high resolution transmission electron microscope study of lead sulfide nanocrystal quantum dots （NCQDs） dispersed on electron-transparent silicon nanopillars that enables nearly atomically-resolved simultaneous imaging of the entire composite： the quantum dot, the interfacial region, and the silicon substrate. Considerable richness in the nanocrystal shape and orientation with respect to the substrate lattice is observed. The average NCQD-substrate separation is found to be significantly smaller than the length of the ligands on the NCQDs. Complementary photoluminescence measurements show that light emission from PbS NCQDs on silicon is effectively quenched which we attribute to intrinsic mechanisms of energy and charge transfer from PbS NCQDs to Si.展开更多
基金This study is financially supported by the National Natural Science Foundation of China (No. 60508012)the Natural Sci-ence Foundation of Zhejiang Province (No. Y106725)+1 种基金the Natural Science Foundation of Ningbo (No. 2006A610048)the Scientific and Technological Project Funding of Zhejiang Province (No. 2006C31040).
文摘A DNA biosensor with [Ru（DA-bpy）3]Cl2（DA-bpy：4,4＇-diamino-2,2＇-bipyridine） （RuL） as the electrochemical probe was prepared on pyrolytic graphite electrode （PGE） through the supramolecular interaction between RuL complex and DNA template. Cyclic voltammetry of RuL-DNA film showed a pair of stable and reversible peaks corresponding to the Ru（Ⅲ）/Ru（Ⅲ） redox potential of-0.165 V versus AglAgCl in pa 7.4 0.1 mol·L^-1Tris-HCl. The electron transfer was expected across the double-strand DNA by an ＂electron tunneling＂ mechanism. When the DNA biosensor was immerged in gold （Ⅲ） buffer solution, the current peak signal （I） of the RuL-DNA supramolecular depressed and △I was linear in the concentration range of Au ion from 1×10^-7 to 2×10^-5 mol·L^-1 with a regression coefficient of 0.9879. The detection limit was 5×10^-8 mol·L^-1. The developed procedures were applied to the analysis of synthetic samples of real materials with good sensitivity and selectivity.
基金Supported by the National Creative Experiment Programs for University Students, Natu-ral Science Foundation of Tianjin (Grant No. 07JCYBJC02000)Foundation for the Author of National Excellent Doctoral Dissertation of China (Grant No. 200732)Program for New Century Excellent Talents in University (Grant No. NCET-07-0463)
文摘Four novel lanthanide-based coordination polymers, [Ln(PBDC)(HPBDC)(H2O)3] (H2PBDC=p-carboxylphenoxyacetate; Ln = La (1), Pr (2), Nd (3)) and [La2(PBDC)3(H2O)4] (4), have been prepared through hydrothermal synthetic methods. Compounds 1―3 are isomorphous and exhibit one-dimensional (1D) chain-like motifs, while compound 4 features a complicated three-dimensional (3D) architecture, which is designed and synthesized based on the inspiration from the structure characterization of compound 1. Under the similar reaction conditions, the carboxyl in compound 1 may be further deprotonated by adding the organic base of 2,2'-bipyridine. This subtle change caused a significant difference in the structures, from 1D chain of 1 to a 3D structure of 4. In addition, IR, UV-Vis, TGA and magenetic properties are also investigated in this paper.
文摘We report on a cross-sectional high resolution transmission electron microscope study of lead sulfide nanocrystal quantum dots （NCQDs） dispersed on electron-transparent silicon nanopillars that enables nearly atomically-resolved simultaneous imaging of the entire composite： the quantum dot, the interfacial region, and the silicon substrate. Considerable richness in the nanocrystal shape and orientation with respect to the substrate lattice is observed. The average NCQD-substrate separation is found to be significantly smaller than the length of the ligands on the NCQDs. Complementary photoluminescence measurements show that light emission from PbS NCQDs on silicon is effectively quenched which we attribute to intrinsic mechanisms of energy and charge transfer from PbS NCQDs to Si.
