The interaction between Ag+ and human serum albumin (HSA) has been intensively studied by means of equilibrium dialysis, ligand-to-metal charge transition (LMCT) bands, circular dichroism (CD) and Raman spectroscopy. Scatchard analysis of the results of 1 equilibrium dialysis indicates the presence of two types of binding sites for Ag+ on HSA, and the orders of magnitude of binding stability 54 constants are found to be 10 5 and 10 4, respectively. During the binding process, a gradual increase in absorbance values of LMCT bands is observed with time-scanning UV absorption spectra, implying the Ag(Ⅰ) centers are continually formed in HSA. The time-scanning CD1 spectra provide evidence that the binding of Ag+ induces HSA to undergo a slow rearrangement of tertiary structure, and to change from 11 the original conformation in the absence of Ag (B-state) to conformation binding with Ag (A-state). The rate constants and activation free energy of A-B transition are calculated. The Raman spectrum of Ag(Ⅰ)-HSA system shows distinct vibration bands at 224 and 246 21cm in the low-frequency region, which significantly reveal the formation of Ag-S and Ag-N bonds. In addition, the electrostatic 1 interaction between Ag+ and negatively charged oxygen is also detected with Raman spectroscopy.

A notable hysteretic effect has been observed in the interaction of Co(Ⅱ) with human serum albumin (HSA) or bovine serum albumin (BSA) using UV-Visible spectrometry at physiological pH (7.43), which shows that the binding between Co(Ⅱ) and HSA or BSA may induce a slow transition of HSA or BSA from the conformation of weaker affinity for Co(Ⅱ) to one of stronger affinity (A-B transition). The rate constants and activation parameters of this transition were measured and are discussed. It is inferred that such a conformation transition may occur due to the binding of the first Co(Ⅱ) ion with the peptide segment of N-terminal residues 1-3, which results in a 'hinged movement' of the relatively hydrophobic 'valley' in the IA subdomain. This process leads to a slow conformational transition in the albumins, makes the other binding sites of Co(Ⅱ) exposed, and shows a positive cooperativity effect. The LMCT (ligand-to-metal charge transition) bands of the Co(Ⅱ)-HSA and Co(Ⅱ)-BSA systems also show a kind of hypochromic effect featuring a dipole-dipole interaction mechanism. This phenomenon is rarely reported.

The hydrothermal reaction of norfloxacin (H-Norf) with NH4VO3 yields an unprecedented neutral nanosized molecular square grid containing a direct coordinate bond between quinololine drug and V(Ⅱ), V(Norf)2·2H2O 1, which is characterized by single Xray determination and IR spectrum as well as TGA.

The aminosilane-modified magnetite nanoparticles were synthesized by the coprecipitation and surface modification with 3-aminopropyltriethoxysilane (APTTS). The superparamagnetic APTTS/Fe3O4 nanospheres with an average diameter of 10nm were characterized significantly with functional group, well dispersion and stabilization in aqueous fluids, as well as a maximized saturation magnetization of 63.54emu/g.

The reaction of picolinic acid (Hpic) and (n-Bu4N)4[MosO26] in the presence of CH3CN gave a supramolecular compound (n-Bu4N)2[Mo2O6(pic)2] (1), and its structure was characterized by elemental analysis, IR spectra and single crystal Xray diffraction analysis. The single crystal X-ray diffraction study shows that the crystal is in monocnnic crystal system, P21/c space group with cell parameters a=0.9941 (2), b=1.3719(2), c=1.8824(2)nm, β=100.840(10)°, Mr=508.50, V=2.5214(9)nm3, F(000)=1072. Compound 1 is a dimer through two μ2-O bridging to two MoO3 (pic)-unit, then connected one-dlmensional anion-chain by undassical hy-drogen bonding, and the anion-chain across the channels formed via (n-Bu4N)+ cations. By means of undassical hydrogen bonding, the anion-chain and cationchannels assemble into three-dimensional supramolecular networks.