A renewable copper electrode as an amperometric flow detector for nitrate determination in mineral water and soft drink samples

TALANTA

卷:80

Article

Gamboa, Juan C. M.¹  Pena, Roselyn C.¹  Paixao, Thiago R. L. C.²  Bertotti, Mauro¹ 

[1] Univ Sao Paulo, Inst Quim, BR-05508900 Sao Paulo, Brazil

[2] Univ Fed ABC, Ctr Ciencias Nat & Humanas, BR-09210170 Santo Andre, SP, Brazil

关键词: Nitrate;    Nitrite;    Flow injection analysis;    Renewable copper surface;    Mineral water;    Soft drink;   

DOI  :  10.1016/j.talanta.2009.07.028

来源: Elsevier

【 摘 要 】

A novel approach was developed for nitrate analysis in a FIA configuration with amperometric detection (E=-0.48 V). Sensitive and reproducible current measurements were achieved by using a copper electrode activated with a controlled potential protocol. The response of the FIA amperometric method was linear over the range from 0.1 to 2.5 mmol L-1 nitrate with a detection limit of 4.2 mu mol L-1 (S/N = 3). The repeatability of measurements was determined as 4.7% (n=9) at the best conditions (flow rate: 3.0 mL min(-1), sample volume: 150 mu L and nitrate concentration: 0.5 mmol L-1) with a sampling rate of 60 samples h(-1). The method was employed for the determination of nitrate in mineral water and soft drink samples and the results were in agreement with those obtained by using a recommended procedure. Studies towards a selective monitoring of nitrite were also performed in samples containing nitrate by carrying out measurements at a less negative potential (-0.20 V). (C) 2009 Elsevier B.V. All rights reserved.

【 授权许可】

Free