ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Flow injection spectrofluorimetric determination of iron(III) in water using salicylic acid

Adem Asan, Muberra Andac, and Ibrahim Isildak

Department of Chemistry, Faculty of Science, Ondokuz Mayis University, 55139 Kurupelit-Samsun, Turkey

E-mail: aasan@omu.edu.tr

Received: 6 October 2009  Revised: 17 December 2009  Accepted: 18 December 2009

Abstract: A simple and fast flow injection fluorescence quenching method for the determination of iron in water has been developed. Fluorimetric determination is based on the measurement of the quenching effect of iron on salicylic acid fluorescence. An emission peak of salicylic acid in aqueous solution occurs at 409 nm with excitation at 299 nm. The carrier solution used was 2 × 10⁻⁶ mol L⁻¹ salicylic acid in 0.1 mol L⁻¹ NH₄⁺/NH₃ buffer solution at pH 8.5. Linear calibration was obtained for 5–100 μg L⁻¹ iron(III) and the relative standard deviation was 1.25 % (n = 5) for a 20 μL injection volume iron(III). The limit of detection was 0.3 μg L⁻¹ and the sampling rate was 60 h⁻¹. The effect of interferences from various metals and anions commonly present in water was also studied. The method was successfully applied to the determination of low levels of iron in real samples (river, sea, and spring waters).

Keywords: flow injection analysis - iron(III) - fluorescence quenching - salicylic acid

Full paper is available at www.springerlink.com.

DOI: 10.2478/s11696-010-0025-7

Chemical Papers 64 (4) 424–428 (2010)