Trace Levels Determination of Ammonium by Flow Injection Analysis Using Gas-Diffusion and Capacitively Coupled Contactless Conductivity Detection

Author(s)

Braz, Henrique L. ^[1] ; Ito, Debora T. ^[1] ; Fracassi da Silva, Jose A. ^[2] ; do Lago, Claudimir L. ^[3] ; Pedrotti, Jairo J. ^[1]

Affiliation

^[1] Univ Presbiteriana Mackenzie, Ctr Ciencias & Humanidades, BR-01302907 Sao Paulo - Brazil

^[2] Univ Estadual Campinas, Inst Quim, BR-13083970 Campinas, SP - Brazil

^[3] Univ Sao Paulo, Inst Quim, BR-05586900 Sao Paulo - Brazil

• Document type: Journal article
• Source: Electroanalysis; v. 23, n. 11, p. 2594-2600, NOV 2011.
• Web of Science Citations: 13

Abstract

A sensitive analytical method based on gas-diffusion flow injection system for ammonium ion determination at trace levels with capacitively coupled contactless conductivity detection (C(4)D) is described. The effects of the chemical composition of the acceptor stream, operating frequency of the conductivity detector, acceptor and donor flow rates, injected volume, and some potential interferents were evaluated. By injecting 100 mu L samples, the analytical method showed linear response for ammonium from 2.0 up to 100 mu mol L(-1) and a limit of detection of 0.8 mu mol L(-1) (14 ppb). At a flow rate of 0.10 mL min(-1) for the acceptor solution, an analytical throughput of 35 injections per hour was achieved. The new flow injection system was successfully applied for ammonium determination in rainwater from Sao Paulo city. (AU)

• FAPESP's process: 08/57805-2 - Institute of Bioanalytics
• Grantee: Lauro Tatsuo Kubota
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 08/53868-0 - Synthesis and chacterization of novel materials strategically structured and organized to be applied in analytical and photonic devices
• Grantee: Lauro Tatsuo Kubota
• Support Opportunities: Research Projects - Thematic Grants