Molecular Interactions Between The Platinum Complexes And DNA In Vitro Studied By Atomic Force Microscope

Platinum complexes are a class of major anticancer drugs. It is a hot topic that to design, synthesize and screen new anticancer drugs with the characteristics of high activity, low toxicity and broad antitumor spectrum. The anticancer pharmacology and mechanism of platinum complexes have been explored and studied, but a lot of interaction procedures are still not clear. Many direct and indirect evidences indicate that DNA is the effect target of platinum complexes, which can result in disorder of DNA replication and inhibit the cellular cleavage. Studying interactions between DNA and platinum complexes can avail to the cognition of the anticancer drugs’action mechanism at the molecular level so as to provide the more scientific guidance for designing, synthesizing and screening new anticancer drugs with the characteristics of high activity, low toxicity and broad antitumor spectrum.1. We used atomic force microscope to assay the interaction between the cisplatin without chloridion and DNA. Along with the growth of the action time, DNA chain appear more and more nodes, DNA chain gradually agglutinate globular structure, through the measurement that height is more and more big.This showed that there were electrostatic force and matingreaction between the cisplatin and DNA.2. DNA condensation was found, according to the AFM topography, which indicated there was electrostatic force between the carboplatin and DNA. After the carboplatin and DNA was mixed fully together, there was a weak hypochromic effect and DNA characteristic absorption peak shift to the long wave, which could be seen in the result of ultraviolet spectum, indicating that carboplatin might interact with DNA, and bind to DNA strands.The results of this paper will provide the scientific basis for designing, synthesizing and screening new platinum complexes.We conclude that the platinum complexes and DNA can interact with each other by means of electrostatic interaction and matingreaction. Furthermore, the action time is one of the important factors which can influence these interactions. Researching the interaction between the platinum complexes and DNA can provide the guidance for the development of effective anticancer drugs in the theory.