Article

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

Chinese Academy of Science Graduate Uniresity Beijing China
Science in China Series B Chemistry (Impact Factor: 1.2). 01/2009; 52(10):1677-1682. DOI: 10.1007/s11426-009-0231-8

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 H2O2 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.

Keywordson-line method-electrochemical biosensor-hypoxanthine-rat brain

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