A simple and novel method for evaluating the concentration of antioxidants in complex biological fluids such as rat brain has been developed based on the interaction of dye-labeled DNA and polydopamine (PDA). Due to the interaction between single-strand DNA and PDA, the fluorescence of dye-labeled DNA (donor) was quenched by PDA (acceptor) to the fluorescence “off” state through  fluorescence resonance energy transfer (FRET). However, various antioxidants, such as glutathione (GSH),cysteine (Cys), ascorbic acid (AA)and homocysteine (Hcys), would block the spontaneous oxidative polymerization of DA to form PDA, resulting in the freedom of FITC-DNA and leading to the fluorescence “on” state. The sensing system showed great sensitivity for the monitoring of antioxidants in a fluorescent “turn on” format. The new strategy also exhibited great selectivity and is free from the interferences of metal ions, amino acids and the biological species commonly existing in brain systems. Hence, by combining the microdialysis technique, the present method has been successfully applied to monitor the dynamic changes of the striatum antioxidants in rat cerebrospinal microdialysates during the normal/ischemia/reperfusion process. This work establishes a new and effective platform for in vivo monitoring antioxidants in cerebral ischemia model, which is a promising platform for the research of brain chemistry, neuroprotection, physiological and pathological events.

Selective and sensitive monitoring antioxidants in the rat brain based on the dye-labeled DNA/polydopamine conjugates

254th National Meeting (2017)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.