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)

Abstract

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, NaBH_4, 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%.

Keywords:

• Flow injection analysis (FIA)
• hydride generation atomic absorption spectrometry (HG-AAS)
• magnetic solid phase extraction (MSPE)

Disclosure statement

The authors report there are no competing interests to declare.

Additional information

Funding

This work was supported by the Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - Brazil (CAPES) Finance Code 001; and Fundação de Amparo à Pesquisa no Rio de Janeiro (FAPERJ) under grant numbers E-26/202.552/2019, E-26/202.755/2019, E-26/010.002212/2019; and the Universidade do Estado do Rio de Janeiro (Programa Pró-Ciência). JSG and ASL have research scholarship from UERJ (Programa Pró-Ciência), and CNPq (grant numbers 302465/2018-9, 304869/2019-8).