Sensitive and ultra-fast determination of arsenic(III) by gas-diffusion flow injection analysis with chemiluminescence detection

• Published in: Analytica chimica acta 2007-01, Vol.583 (1), p.72-77
• Main Authors: Lomonte, Cristina, Currell, Matthew, Morrison, Richard J.S., McKelvie, Ian D., Kolev, Spas D.
• Format: Article
• Language: English
• Subjects: Analytical chemistry; Arsenic - analysis; Arsenic determination; Arsine; Chemical and thermal methods; Chemiluminescence detection; Chemistry; Electrochemistry; Exact sciences and technology; Gas-diffusion flow injection analysis; Luminescence; Ozone; Reproducibility of Results; Sensitivity and Specificity; Solutions; Spectrometry, Fluorescence; Water - analysis
• ISSN: 0003-2670; 1873-4324
• DOI: 10.1016/j.aca.2006.09.049

A novel chemiluminescence gas-diffusion flow injection system for the determination of arsenic(III) in aqueous samples is described. The analytical procedure involves injection of arsenic(III) samples and standards into a 0.3 mol L −1 hydrochloric acid carrier stream which is merged with a reagent stream containing 0.2% (w/v) sodium borohydride and 0.015 mol L −1 sodium hydroxide. Arsine, generated in the combined carrier/reagent donor stream, diffuses across the hydrophobic Teflon membrane of the gas-diffusion cell into an argon acceptor stream and then reacts with ozone in the flow-through chemiluminescence measuring cell of the flow system. Under optimal conditions, the method is characterized by a wide linear calibration range from 0.6 μg L −1 to 25 mg L −1, a detection limit of 0.6 μg L −1 and a sample throughput of 300 samples per hour at 25 mg L −1 and 450 samples per hour at 25 μg L −1.