Papers by Keyword: Metal Coordination

Abstract: Using the complex of quercetin and Ni+2 (quercetin-Ni+2) as template (quercetin is a kind of flavonoids which are important active ingredients of Chinese herbs.), methacrylic acid as functional monomer and ethylene glycol dimethacrylate as cross-linker, metal-complexing template polymer has been prepared in the mixed solution of methanol and tetrahydrofuran by molecular imprinting technique. The coordination structure and complex ratio between quercetin and Ni+2 were studied by UV-visible spectroscopy, and the ternary complexation of quercetin, Ni+2 and methacrylic acid was verified by similar methods. Selective adsorption experiments for substrates indicated that compared with quercetin’s structural analogs (baicalein and baringenin), quercetin-Ni+2 template polymer prepared with appropriate amount of cross-linker exhibited significant adsorption selectivity for quercetin in the presence of Ni+2. The separation factors were 3.915 and 5.443 respectively, which also showed that adsorption capacity was greatly influenced by the amount of cross-linker.

Abstract: Tumor targeting of plasmid DNA was achieved through the conjugation of dextran derivative with chelate residue based on metal coordination. Spermine (Sm) was chemically introduced to the hydroxyl groups of dextran to obtain dextran-Sm derivative. A negative zeta potential of plasmid DNA became almost 0 mV by the Zn2+-coordinated conjugation with the dextran-Sm When the dextran-Sm-plasmid DNA conjugate with Zn2+ coordination was intravenously injected to mice subcutaneously bearing Meth-AR-1 fibrosarcoma, the dextran- Sm-plasmid DNA conjugate significantly enhanced the level of gene expression in the tumor, in contrast to free plasmid DNA..