Artículos de revistas
Effects of EDTA on signal stability during electrochemical detection of acetaminophen
Registro en:
Journal Of Pharmaceutical And Biomedical Analysis. Pergamon-elsevier Science Ltd, v. 34, n. 5, n. 871, n. 878, 2004.
0731-7085
WOS:000220512100004
10.1016/j.jpba.2003.11.005
Autor
de Carvalho, RM
Freire, RS
Rath, S
Kubota, LT
Institución
Resumen
The use of EDTA in the medium to avoid the passivation of a solid electrode during electrochemical analysis of acetaminophen is presented in this work. The performance of this system was investigated with respect to pH, applied potential and supporting electrolyte concentration. The major advantage in using EDTA in the supporting electrolyte is the significant increase in sensitivity, precision and stability of the measurements, when compared to the system in absence of the chelating agent. The sensitivity increases 5.5 times (21.5 and 3.9 mA 1 mol(-1) in the presence and the absence of EDTA, respectively), the repeatability (n = 20) is 3.5 times better, expressed by within-run-precision of 4.0% for 6.0 x 10(-5) mol l(-1) acetaminophen in the presence of EDTA while, in its absence, the within-run-precision was higher than 14%. Moreover, the system showed excellent stability, allowing more than 120 measurements with no significant changes. (C) 2003 Elsevier B.V. All rights reserved. 34 5 871 878