Synthesis and biological evaluation of Germanium(IV)-polyphenol complexes as potential anti-cancer agents

Germanium (Ge) is considered to play a key role in the pharmacological effects of some medicinal plants. Here, two new Ge(IV)-polyphenol complexes were synthesized and measured for their potential biological activities. The results indicated that these Ge(IV)-polyphenol complexes possessed great anti-oxidative activities, both showing stronger hydroxyl scavenging effects than their corresponding ligands. We also demonstrated the strong intercalating abilities of Ge(IV)-polyphenol complexes into calf thymus-DNA molecules. In addition, these two Ge(IV)-polyphenol complexes showed strong proliferative inhibition effect on HepG2 cancer cells. Moreover, the morphological changes in HepG2 cells induced by Ge(IV)-polyphenol complexes were detected by atomic force microscopy. All these results collectively suggested that Ge(IV)-polyphenol complexes could be served as promising pharmacologically active substances against cancer treatment.