Electrochemical sensors for direct reagentless measurement of superoxide production by human neutrophils.
Electrochemical sensors based on immobilised cytochrome c or superoxide dismutase for the measurement of superoxide radical production by stimulated neutrophils are described. Cytochrome c was immobilised covalently at a surface-modified gold electrode and by passive adsorption to novel platinised activated carbon electrodes (PACE). The reoxidation of cytochrome c at the electrode surface upon reduction by superoxide was monitored using both xanthine/xanthine oxidase and stimulated neutrophils as sources of the free radical. In addition, bovine Cu/Zn superoxide dismutase was immobilised to PACE by passive adsorption and superoxide, generated by xanthine/xanthine oxidase, detected by oxidation of hydrogen peroxide produced by the enzymic dismutation of the superoxide radical. A biopsy needle probe electrode based on cytochrome c immobilised at PACE and suitable for continuous monitoring of free radical production was constructed and characterised.
McNeil
C J
CJ
Department of Clinical Biochemistry, Medical School, University of Newcastle upon Tyne, UK.
Greenough
K R
KR
Weeks
P A
PA
Self
C H
CH
Cooper
J M
JM
D001706:Biopsy; D003574:Cytochrome c Group; D004563:Electrochemistry / Q000295:instrumentation*; D004566:Electrodes; D006046:Gold; D006801:Humans; D009504:Neutrophils / Q000378:metabolism*; D010984:Platinum; D016897:Respiratory Burst; D013481:Superoxides / Q000032:analysis*; D019820:Xanthine; D014969:Xanthine Oxidase; D014970:Xanthines
D003574:Cytochrome c Group; D014970:Xanthines; D013481:Superoxides; D019820:Xanthine; D010984:Platinum; D006046:Gold; D014969:Xanthine Oxidase