Flow injection biamperometric determination of chloramine-T in environmental, pharmaceutical and veterinary samples

• Published in: Analytica chimica acta 2000-02, Vol.407 (1), p.187-192
• Main Authors: CATALA ICARDO, M, GIMENEZ ROMERO, D, GARCIA MATEO, J. V, MARTINEZ CALATAYUD, J
• Format: Article
• Language: English
• Subjects: Analytical chemistry; Biamperometry; Chemistry; Chloramine-T; Clinical analysis; Electrochemical methods; Exact sciences and technology; Flow injection analysis (FIA); Pharmaceutical analysis; Waste water analysis
• ISSN: 0003-2670; 1873-4324
• DOI: 10.1016/S0003-2670(99)00791-6

A flow injection assembly for the determination of chloramine-T is proposed. The sample (213 μl) is inserted into the carrier, de-ionized water flowing at 4.1 ml min −1. This carrier merges with a mixture of potassium iodide and sulphuric acid, and the resulting solution flows to the flow cell through a reactor 66 cm long. The chloramine-T oxidises the iodide to tri-iodide. The resulting iodide/iodine ratio is biamperometrically tested. The calibration graph is linear up to 65 μg ml −1 chloramine-T; the limit of detection is 0.5 μg ml −1; the relative standard deviation (r.s.d) of the calibration slope is 2.8% for a series of eight independent calibrations. The r.s.d. of a series of 74 peaks for 40 μg ml −1 chloramine-T) is 0.8%, and the sample throughput 220 h −1. Few foreign substances interfered. The method is applied to pharmaceutical, veterinary and waste water samples.