Amperometric biosensor for the quantification of gentisic acid using poliphenol oxidase modified carbon paste electrode

M. L. PEDANO AND G. A. RIVAS.

TALANTA

Elsevier

Año: 2000 vol. 53 p. 485 - 495

0039-9140

The affinity of mushroom polyphenol oxidase (PPO) towards gentisic acid (GA), a metabolite of acetyl salicylic acid (ASA), is demonstrated by spectrophotometry and by electrochemical techniques. The enzyme can selectively recognize GA even in the presence of large excess of ASA and its metabolic derivatives (salicylic acid (SA) and salicyluric acid (SUA)). At 0.150 V, the sensitivity is (6.190.1)¡¡104 NAM1, the response is linear up to 2.0¡¡104 M and the detection limit is 5.0¡¡105 M. The kinetic parameters, obtained from Eadie¨CHofstee plots, are Imax-51.4 nA and Km app-6.7¡¡104 M.0.150 V, the sensitivity is (6.190.1)¡¡104 NAM1, the response is linear up to 2.0¡¡104 M and the detection limit is 5.0¡¡105 M. The kinetic parameters, obtained from Eadie¨CHofstee plots, are Imax-51.4 nA and Km app-6.7¡¡104 M.¡¡104 M and the detection limit is 5.0¡¡105 M. The kinetic parameters, obtained from Eadie¨CHofstee plots, are Imax-51.4 nA and Km app-6.7¡¡104 M.Imax-51.4 nA and Km app-6.7¡¡104 M.-6.7¡¡104 M.