Improving the anti-tumor effect of genistein with a biocompatible superparamagnetic drug delivery system.

The practical application of genistein as a low toxicity chemotherapeutic drug is hindered by many of its in vivo properties. To overcome these obstacles, a new multifunctional drug delivery system is developed, which is based on covalently attaching genistein onto Fe3O4 nanoparticles coated by cross-linked carboxymethylated chitosan (CMCH). The structure of the Fe3O4-CMCH-genistein nano-conjugate was confirmed by transmission electron micrographs (TEM), X-ray diffraction (XRD) and Fourier-transfer infrared (FT-IR) spectroscopy. The nano-conjugate shows good water solubility and superparamagnetic properties with a saturation magnetization of 55.1 emu/g. The effects of free genistein and FeO4-CMCH-genistein nano-conjugate on the proliferation and apoptosis of gastric cancer cell line SGC-7901 were investigated by MTT assay and flow cytometry (FACS). MTT results indicate that the Fe3O4-CMCH-genistein nano-conjugate exhibits a significantly enhanced inhibition effect to the SGC-7901 cancer cells than the free genistein. FACS data suggests that the inhibition on cell proliferation of the nano-conjugate is related with an induced apoptosis process. This drug delivery system is promising for future multifunctional chemotherapeutic application that combines drug release and magnetic hyperthermia therapy.

4,4'-{[1,1'-Methyl-enebis(naphthalene-2,1-di-yl)]bis-(-oxymethyl-ene)}di-benzo-nitrile.

There are two independent mol-ecules in the asymmetric unit of the title compound, C(37)H(26)N(2)O(2). The crystal structure is stabilized by a weak intra-molecular hydrogen bond as well as C-H⋯π inter-actions.

2-(1H-Tetra-zol-5-yl)benzonitrile.

The title compound, C(8)H(5)N(5), was synthesized from phthalonitrile. The benzonitrile and tetra-zole rings are inclined at a dihedral angle of 37.14 (11)°. In the crystal structure, inter-molecular N-H⋯N hydrogen bonds link the tetra-zole rings of adjacent mol-ecules, forming chains along the a axis.

4-(1H-Benzimidazol-2-yl)benzonitrile.

The mol-ecule of the title compound, C(14)H(9)N(3), is essentially planar, the dihedral angle formed by the benzimidazole ring system with the benzene ring being 3.87 (3)°. In the crystal packing, mol-ecules are linked into zigzag chains running parallel to the b axis by inter-molecular N-H⋯N hydrogen-bond inter-actions.

4-Amino-3-phenyl-1H-1,2,4-triazole-5(4H)-thione.

In the title compound, C(8)H(8)N(4)S, the planar triazole ring forms a dihedral angle of 13.7 (2)° with the phenyl ring. The crystal structure is stabilized by inter-molecular N-H⋯S hydrogen-bond inter-actions, linking the mol-ecules into chains along the a axis.

4-[(E)-(3-Methyl-5-thioxo-4,5-dihydro-1H-1,2,4-triazol-4-yl)imino-meth-yl]benzonitrile.

In the title compound, C(11)H(9)N(5)S, the dihedral angle between the mean planes of the thione-substituted triazole ring and benzonitrile ring is 4.28 (3)°. Inter-molecular N-H⋯S hydrogen bonds link the mol-ecules together into characteristic dimers.

Dichloridobis(3,5-dimethyl-1H-pyrazol-4-amine-κN)cobalt(II).

In the title compound, [CoCl(2)(C(5)H(9)N(3))(2)], the Co(II) atom adopts a slightly distorted tetra-hedral coordination geometry provided by two chloride anions and two N atoms from the organic ligands. The dihedral angle between the pyrazole rings is 85.91 (10)°. In the crystal structure, mol-ecules are linked into a three-dimensional network by inter-molecular N-H⋯N and N-H⋯Cl hydrogen-bonding inter-actions.