A Novel Reagentless Biosensor Constructed by Layer-by-Layer Assembly of HRP and Nile Blue Premixed with Polyanion

A novel reagentless biosensor constructed by the organic dye nile blue (NB) and horseradish peroxidase (HRP) has been fabricated via layer-by-layer (LBL) self-assembly technique. NB premixed with polyanion poly (sodium-p-styrenesulfonate) (PSS) acts as the mediator between the immobilized HRP and the electrode surface. The response of the biosensor to hydrogen peroxide has been investigated. The linear range of the biosensor to hydrogen peroxide was from 0.20 mmol/L to 7.03 mmol/L with a sensitivity of 8.45 μA/(mmol/L).     

Solvent-controlled structural variation from 1D+2D→3D network with coexistence of polycatenation and polythreading to the 2D→3D polythreaded array

This article represents two types of entanglements, [Co₂(bibp)(BTB)₂][Co(bibp)₂(H₂O)₂] (1) and [Co₃(bibp)₂(H₂O)₂(BTB)₂]·2H₂O·2DMF (2) (bibp = 4,4′-bis(1-imidazolyl)biphenyl and H₃BTB = 1,3,5-tris(4-carboxyphenyl)benzene), which are 2-D→3-D polycatenated frameworks formed by parallel catenation of 1-D+2-D→2-D polythreaded motifs based on the double-layered sheet penetrated by ribbons of rings (1) and a 2-D→3-D mutual polythreading of three double-layered sheets with dangling arms (2), which is assembled by the same initial materials by simply changing the volume ratio of water/DMF medium.     

A Novel 3D Supramolecular Network Constructed from [Cu(4,4'-bipyridine)(O_2CMe)_2]_2 Molecular Ladders by Hydrogen Bonding

1 INTRODUCTION In recent years, the assembly of extended supra- molecular architectures from molecular building units has yielded a new generation of materials with diverse network topologies[1～3]. A number of such frameworks have been found to exhibit fascinating physical and chemical properties. The investigation of hydrogen bonding is important for many practical applications, such as the design of antibiotics and development of new materials with programmed properties[4]. A great va…     

One-Dimensional Network Constructed by Salicylate and Phenanthroline Ligands with Copper(II)

ＩｎｔｒｏｄｕｃｔｉｏｎＳａｌｉｃｙｌｉｃａｃｉｄ (Ｈ2 ｓａｌ)ｉｓａｎｉｎｔｅｒｅｓｔｉｎｇｖｅｒｓａｔｉｌｅｌｉｇ ａｎｄａｎｄｉｔｓｃｏｍｐｌｅｘｅｓａｒｅｏｆｃｏｎｔｉｎｕｏｕｓｉｎｔｅｒｅｓｔｆｒｏｍｂｏｔｈｓｔｒｕｃｔｕｒａｌａｎｄｂｉｏｌｏｇｉｃａｌｖｉｅｗｐｏｉｎｔｓ .1 2 Ｈ2 ｓａｌｈａｓｔｗｏｆｕｎｃｔｉｏｎａｌｇｒｏｕｐｓ ,ｔｈｅｃａｒｂｏｘｙｌａｔｅａｎｄｐｈｅｎｏｘｉｄｅ ,ｗｈｉｃｈｈａｖｅｂｅｅｎｗｉｄｅｌｙｅｍｐｏｌｙｅｄｉｎｔｈｅｓｙｎｔｈｅｓｉｓｏｆｍｏｎｏｎｕｃｌ…     

One—dimensional Network Constructed by Salicylate and Phenanthroline Ligands with Copper（Ⅱ）

A novel complex,[Cu2(phen)(sal)(Hsal)2]n(1),was synthesized and structurally characterized.The basic dimeric units are hold by sal ligands and extended into 1-D network.The carboxylate grougs of salicylates coordinate to the central ion in three different coordination modes:chelating,bridging and bridging-chelating.In the case of bridging-chelating of the carboxylate group of the salicylate,all three oxygen atoms of salicylate are bidentately coordinated to copper ion,namely,μ4-η^3 binding mode.     

Synthesis and Crystal Structure of a Novel 3D Magnesium(II) Coordination Polymer Constructed by Flexible Benzene-1,4-dioxyacetate

1 INTRODUCTION The coordination chemistry of the alkaline-earth metals has remained a largely underdeveloped area[1, 2]to date. Also calcium(II) and magnesium(II) ions are the essentially biological elements and play an im- portant role in DNA and protein syntheses. Although the transition metal carboxylates have been widely in- vestigated[3, 4], the reports on magnesium complexes with carboxylate ligands are very rare[5]. The flexible phenylenedioxydiacetic acids (BDOAH2), especial…     

Synthesis and Crystal Structure of a Novel Manganese Coordination Polymer Constructed by 3,5-Dimethylbenzoic Acid with 4,4'-Bipyridine

1 INTRODUCTION There has been extensive interest in manganese complexes containing carboxylate ligands due to the richness in structural chemistry and potential appli- cations in catalysis[1～6], for example, some highly efficient manganese catalysis mimics[7, 8]. Further- more, 4,4?-bipy is an excellent bridging ligand, and so far a number of one-, two- and three-dimensional infinite metal-4,4?-bipy frameworks have already been generated[9, 10]. However, of the above-mentio- ned framework…     

Synthesis and Crystal Structure of a Novel 1D Magnesium(II) Coordination Polymer Constructed by L-Cysteic Acid

A novel coordination polymer [Mg(L)(H2O)2]·H2O] (LH2 = L-cysteic acid) has been synthesized and characterized by elemental analysis, IR and single-crystal X-ray diffraction. The crystal crystallizes in orthorhombic system, space group P212121, with a = 5.962(3), b = 11.224(6), c = 13.664(7) , V = 914.3(8) 3, Z = 4, Mr = 245.50, Dc = 1.783 g/cm3, μ = 0.445 mm–1, flack parameter = 0.32(16), F(000) = 512, the final R = 0.0458 and wR = 0.1172 for 1578 observed reflections with I > 2σ(I). The Mg(II) atom shows an octahedral geometry defined by two carboxyl O atoms from two different L-cysteic acid ligands, one carboxyl O atom and one amino N atom from the adjacent ligand, and two aqua ligands. The Mg(II) atoms are bridged by L-cysteic acid ligands, leading to a 1D infinite zigzag chain. In the structure there are extensive hydrogen bonds, through which the complex completes its 3D framework structure.     

Synthesis and Crystal Structure of a Novel 1D Magnesium （Ⅱ） Coordination Polymer Constructed by L-Cysteic Acid

A novel coordination polymer [Mg(L)(H2O)2]·H2O] (LH2=L-cysteic acid) has been synthesized and characterized by elemental analysis, IR and single-crystal X-ray diffraction.The crystal crystallizes in orthorhombic system, space group P212121, with a=5.962(3), b=11.224(6), c=13.664(7)(A), V=914.3(8) (A)3, Z=4, Mr=245.50, Dc=1.783 g/cm3,μ=0.445 mm-1,flack parameter=0.32(16), F(000)=512, the final R=0.0458 and wR=0.1172 for 1578 observed reflections with I ＞ 2σ(Ⅰ). The Mg(Ⅱ) atom shows an octahedral geometry defined by two carboxyl O atoms from two different L-cysteic acid ligands, one carboxyl O atom and one amino N atom from the adjacent ligand, and two aqua ligands. The Mg(Ⅱ) atoms are bridged by L-cysteic acid ligands, leading to a 1D infinite zigzag chain. In the structure there are extensive hydrogen bonds,through which the complex completes its 3D framework structure.     

Synthesis and Crystal Structure of a Novel 1D Magnesium (Ⅱ) Coordination Polymer Constructed by L-Cysteic Acid

A novel coordination polymer [Mg(L)(H2O)2]·H2O] (LH2=L-cysteic acid) has been synthesized and characterized by elemental analysis, IR and single-crystal X-ray diffraction.The crystal crystallizes in orthorhombic system, space group P212121, with a=5.962(3), b=11.224(6), c=13.664(7)(A), V=914.3(8) (A)3, Z=4, Mr=245.50, Dc=1.783 g/cm3,μ=0.445 mm-1,flack parameter=0.32(16), F(000)=512, the final R=0.0458 and wR=0.1172 for 1578 observed reflections with I ＞ 2σ(Ⅰ). The Mg(Ⅱ) atom shows an octahedral geometry defined by two carboxyl O atoms from two different L-cysteic acid ligands, one carboxyl O atom and one amino N atom from the adjacent ligand, and two aqua ligands. The Mg(Ⅱ) atoms are bridged by L-cysteic acid ligands, leading to a 1D infinite zigzag chain. In the structure there are extensive hydrogen bonds,through which the complex completes its 3D framework structure.     

A Novel Approach to Improve the Detectability of CO2 by GC Analysis

A novel stochastic resonance algorithm was employed to enhance the signal-to-noise ratio (SNR) of signals of analytical chemistry.By using a gas chromatographic data set,it was proven that the SNR was greatly improved and the quantitative relationship between concentrations and chromatographic responses remined simultancously.The linear range was extended beyond the instrumental detection limit.     

A Novel 3D Twofold Zn(Ⅱ) Coordination Polymer Constructed by Mixed Flexible Ligands: Synthesis,Crystal Structure and Fluorescence Property

A new Zn(Ⅱ) coordination polymer, {[Zn(1,3-bip)(oba)]·0.5H_2O}n(1),1,3-bip =1,3-bis(imidazole)propane, H_2oba=4,4?-oxybis(benzoate)), have been synthesized and characterized by single-crystal X-ray diffraction, powder XRD, FTIR, TGA and elemental analysis techniques. The single-crystal X-ray diffraction reveals that complex 1 shows a 3D→3D twofold interpenetrating network that can be described as a 4-connected uninodal net with(65.8) topology. In addition, the photoluminescence property of complex 1 was also investigated at room temperature.     

Synthesis and Crystal Structure of a New 2D Honeycomb-like Cadmium(II) Complex with Tripodal Ligand

ＩｎｔｒｏｄｕｃｔｉｏｎＩｎｔｈｅｐａｓｔｓｅｖｅｒａｌｙｅａｒｓ ,ｃｏｎｓｉｄｅｒａｂｌｅｐｒｏｇｒｅｓｓｈａｓｂｅｅｎａｃｈｉｅｖｅｄｉｎｃｏｎｔｒｏｌｌｉｎｇｔｈｅａｓｓｅｍｂｌｙｏｆｉｎｄｉｖｉｄｕａｌｂｕｉｌｄｉｎｇｂｌｏｃｋｓｉｎｔｏｓｔｒｕｃｔｕｒｅｓｗｉｔｈｓｐｅｃｉｆｉｃｔｏｐｏｌｏｇｉｅｓａｎｄｉｎｔｅｒｅｓｔｉｎｇｐｒｏｐｅｒｔｉｅｓｓｕｃｈａｓｍｏｌｅｃｕｌａｒｒｅｃｏｇｎｉｔｉｏｎ ,ｉｏｎｅｘｃｈａｎｇｅａｎｄｓｅｌｅｃｔｉｖｅｇｕｅｓｔｉｎｃｌｕｓｉｏｎ .1 3 Ｉｔｉｓ…     

2D‐ and 3D‐ Potential Energy Surfaces of β‐(1→3)‐Linked Disaccharides Calculated with the MM3 Force‐Field

The adiabatic conformational surfaces of sixteen 4′,6′,6‐trideoxy‐β‐d‐(1→3)‐linked disaccharides were obtained using the MM3 force‐field. Calculations were carried out on disaccharides with different configurations at C2, C4 and C2′, which are neighbors to the glycosidic linkage, as well as that of the linked carbon (C3). The surfaces were plotted as contour maps and as 2D graphs representing the energy vs. the ψ angle. The resulting maps were similar in each case, indicating that the substituents do not play a major role in the conformational features of these disaccharides. However, the number of minima, the preferred minimum conformation and the flexibility depended on the configurations of the mentioned carbons. Vicinal equatorial substituents tend to decrease the overall flexibility, especially those on C2, although cross over effects were found. The relative stabilities of the minimal energy conformations of the 16 compounds were compared with those of their equivalent α‐linked counterparts. Deviations of the predicted increased stabilities of equatorially substituted compounds over axially substituted ones follow a relationship with their configurations, and consequently can serve to formulate predictive trends.