Determining Mercury in Sediment Samples by Extraction Using a Novel-Chelating Reagent Dithiothreitol (DTT) Followed by Cold Vapor Atomic Fluorescence Spectrometry (CV-AFS)

Journal of the Brazilian Chemical Society

article

Jesus, Robson M. de¹  Brandão, Geovani C.³  Santos, Walter N. L. dos²  Santos, Leila O. dos²  Andrade, Jailson B. de¹ 

[1] Universidade Federal da Bahia (UFBA);Instituto Nacional de Ciência e Tecnologia em Energia e Ambiente (INCT E&A), Universidade Federal da Bahia (UFBA);Departamento de Ciências Exatas e da Terra, Universidade do Estado da Bahia (UNEB);Universidade Federal do Sul da Bahia (UFSB);SENAI-CIMATEC, Centro Universitário

关键词: dithiothreitol;    mercury;    sediments;    cold vapor;    direct Hg analyzer;   

DOI  :  10.21577/0103-5053.20200133

学科分类：内科医学

来源: SciELO

【 摘 要 】

A new analytical protocol has been developed for the determination of mercury in surface sediments using dithiothreitol (DTT) as a new chelating reagent for the extraction. This protocol requires a small sample mass (250 mg), 4.0 mL of a 0.1 M (pH = 9.0) aqueous DTT solution, and sonication for 30 min, followed by cold vapor atomic fluorescence spectrometry (CV-AFS). The limits of detection and quantification determined were 6 and 18 ng g −1 , respectively. The method was validated using three standard reference materials, SRM NIST 1646a, PACS-2, and MESS-3, with recoveries in the range of 102-124%. The new analytical protocol was successfully applied in riverine surface sediments, revealing concentrations in the range of 220-340 ng g −1 . The results obtained by CV-AFS were compared to those obtained by DMA-80 (direct mercury analyzer). The linear regression equation obtained was [CV-AFS] = (0.91 ± 0.07)[DMA-80] + (0.04 ± 0.02), revealing no systematic difference between the analytical methods. Hence, the proposed method does not require the complete digestion of the sediment, and was found to be comprehensive, simple, accurate and suitable to be employed for determination of mercury in sediment samples.

【 授权许可】

CC BY