Electrochemical detection of in situ DNA damage induced by enzyme-catalyzed Fenton reaction. Part I: in phosphate buffer solution

Abstract

We report on a biosensor for the electrochemical detection of the damage of DNA and of antioxidant protecting DNA. The biosensor was constructed by co-immobilization of DNA and glucose oxidase (GOx) on a glassy carbon electrode. Under aerobic conditions, GOx catalyzes the oxidation of glucose, and the hydrogen peroxide produced reacts with ferrous ions in a Fenton-type reaction to generate hydroxy radical. This was validated by UV-vis spectroscopy. The hydroxy radical can cause serious oxidative damage to DNA, and this can be detected by square wave voltammetry of the electroactive indicator Co(bpy) 3 3+. The effects of pH value, incubation time, and the concentration of glucose and ferrous ion were optimized. The effects of the antioxidants ascorbic acid and aloe emodin on DNA damage were also investigated within the concentration range from 0.05 to 200 μM. This work provides an in-vitro model system to mimic the processes in oxidative DNA damage by a simple electrochemical approach.

The antioxidant properties of the chestnut bee pollen extract and its preventive action against oxidatively induced damage in DNA bases

“…DNA, which is an important biomolecule for living organisms, is damaged by the effects of many endogenous and exogenous factors, such as ionizing radiation, reactive oxygen species (ROS), UV light, chemicals, air pollution, and smoke (Chen, Xiong, Zhang, & Wang, ). The main ROS compounds have been responsible for the formation of oxidative damage by attacking macromolecules, such as proteins and DNA.…”