Ultrasensitive Determination of Arsenic in Juvenile Eyeshadow by Novel Dispersive Magnetic Solid-Phase Extraction (MSPE) and Flow Injection Analysis – Hydride Generation Atomic Absorption Spectrometry (FIA-HG-AAS).

A new procedure is reported for arsenic preconcentration in juvenile eyeshadow using maghemite nanoparticles (γ-Fe2O3) and determination by flow injection analysis – hydride generation atomic absorption spectrometry (FIA-HG-AAS). Maghemite nanoparticles were synthesized and characterized using X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and N2 adsorption measurements at −196 °C. The results showed a crystalline size of 9.1 nm and a surface area of 106 m2 g−1. The experimental conditions for the hydride generation system and the preconcentration process were optimized using a central composite design. For hydride generation, the levels of the concentration of the factors HCl, NaBH4, and flow of carrier gas were optimized, with optimal conditions of 4 mol L−1, 1.1% (m/v), and 145 mL min−1, respectively. The optimized conditions obtained for the adsorption process were a pH equal to 5.3, a mass of γ-Fe2O3 of 184 mg, and stirring time of 41 min in the presence of the sample matrix. The enrichment factor was 50, and the limit of detection was 0.9 μg g−1. Recovery values ranged from 75 to 99%. [ABSTRACT FROM AUTHOR]