Plant tissue-based chemiluminescence flow biosensor for determination of unbound dopamine in rabbit blood with on-line microdialysis sampling.

A novel plant tissue-based chemiluminescence (CL) biosensor for dopamine combined with flow injection analysis is presented in this paper. The potato roots act as molecular recognition elements. Dopamine is oxidized by oxygen under the catalysis of polyphenol oxidase in the tissue column to produce hydrogen peroxide, which can react with luminol in the presence of peroxidase of potato tissue to generate CL signal. The CL emission intensity was linear with dopamine concentration in the range of 1x10(-5)-1x10(-7) g/ml and the detection limit was 5.3x10(-8) g/ml (3sigma) with a relative standard deviation of 1.7%. Combined with microdialysis sampling, the biosensor was applied to monitor the variation of dopamine level in the blood of rabbit after the administration of dopamine to demonstrate the favorable resolution and reliability of the system for in vivo on-line monitoring.