Development of a simple, sensitive and inexpensive ion-pairing cloud point extraction approach for the determination of trace inorganic arsenic species in spring water, beverage and rice samples by UV–Vis spectrophotometry

• The CPE was combined with UV–Vis spectrophotometry for detection of inorganic As.
• The method is based on the ion-association of As(V) with acridine orange in presence of tartaric acid at pH 5.0.
• The variables affecting CPE efficiency were extensively optimized.
• A good detection limit of 1.14 μg L−1 for As(V) in a linear range of 4–450 μg L−1 was achieved.
• The study can also be extended to the other matrices and possible sources of contamination.

The determination of inorganic arsenic species in water, beverages and foods become crucial in recent years, because arsenic species are considered carcinogenic and found at high concentrations in the samples. This communication describes a new cloud-point extraction (CPE) method for the determination of low quantity of arsenic species in the samples, purchased from the local market by UV–Visible Spectrophotometer (UV–Vis). The method is based on selective ternary complex of As(V) with acridine orange (AOH+) being a versatile fluorescence cationic dye in presence of tartaric acid and polyethylene glycol tert-octylphenyl ether (Triton X-114) at pH 5.0. Under the optimized conditions, a preconcentration factor of 65 and detection limit (3Sblank/m) of 1.14 μg L−1 was obtained from the calibration curve constructed in the range of 4–450 μg L−1 with a correlation coefficient of 0.9932 for As(V). The method is validated by the analysis of certified reference materials (CRMs).

The experimental steps of the CPE procedure for detection of As(III), As(V) and total As in water, rice and beverage samples.Figure optionsDownload as PowerPoint slide