On-line electrochemical measurements of cerebral hypoxanthine of freely moving rats

Abstract

This study demonstrates an on-line method for continuous measurements of cerebral hypoxanthine in the freely moving rats with integration of selective electrochemical biosensing with in vivo microdialysis sampling. The selective electrochemical biosensing is achieved by using xanthine oxidase (XOD) as the specific sensing element and Prussian blue (PB) as the electrocatalyst for the reduction of H 2 O 2 generated from the oxidase-catalyzed reaction. The method is virtually interference-free from the coexisting electroactive species in the brain and exhibits a good stability and reproducibility. Upon integrated with in vivo microdialysis, the on-line method is well suitable for continuous measurements of cerebral hypoxanthine of freely moving rats, which is illustrated by the measurements of the microdialysates after the hypoxanthine standard was externally infused into the rat brain. This study essentially offers a facile on-line electrochemical approach to continuous measurements of cerebral hypoxanthine and could find some interesting applications in physiological and pathological investigations associated with hypoxanthine.on-line method, electrochemical biosensor, hypoxanthine, rat brain

Recent Advances in Analytical Methodology for in vivo Electrochemistry in Mammals

“…As compared to the oxidase-based biosensors with natural horseradish peroxidase (HRP) as the recognition unit of H 2 O 2 through either ad irect or mediated electron transfero fH RP,t he use of PB as the electrocatalyst for the H 2 O 2 reduction and sensing essentially eliminated the interference from ascorbate and othern eurochemicals. This concept was further extended for online electrochemical sensing of cerebral hypoxanthine with xanthine oxidaseast he recognition unit [72].…”