Hydride generation coupled with thioglycolic acid coated gold nanoparticles as simple and sensitive headspace colorimetric assay for visual detection of Sb(III)

• Published in: Analytica chimica acta Vol. 1004; pp. 67 - 73
• Main Authors: Tolessa, Tesfaye, Tan, Zhi-Qiang, Liu, Jing-Fu
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 03.04.2018; Elsevier BV
• Subjects: Analytical methods; Anthropogenic factors; Antimony; Arsenic; Chemical analysis; Chromogenic reaction; Colorimetry; Detection limits; Drinking water; Environmental protection; Ethylenediamine; Ethylenediaminetetraacetic acids; Feasibility studies; Gold; Gold nanoparticles; Groundwater; Headspace; Headspace colorimetric assay; Health problems; Heart diseases; Hydride generation; Hydrides; Lung cancer; Masking; Mercury; Mercury (metal); Metal ions; Methanol; Nanoparticles; Reagents; Rivers; Sample preparation; Seawater; Surface water; Thioglycolic acid; Water analysis; Water sampling; Hydride generation; Headspace colorimetric assay; Chromogenic reaction; Gold nanoparticles
• ISSN: 0003-2670; 1873-4324
• DOI: 10.1016/j.aca.2017.11.073

Antimony (Sb) is a toxic element which causes different health problems including cardiac problems and lung cancer in humans, and its levels in surface water can be noticeably increased to 100 μg/L typically in the proximity of anthropogenic sources. Thus, besides instrumental techniques, it is of great significance to develop a simple, sensitive and selective analytical method for direct analysis of Sb(III) at trace level without the need of any expensive and/or complicated instrumentations and sample preparation processes. Herein, a simple and sensitive headspace colorimetric assay was developed for the detection of Sb(III) by hydride generation coupled with thioglycolic acid functionalized gold nanoparticles (TGA-AuNPs). Sb(III) in the 30 mL sample solution was converted into its volatile form (SbH3) through hydride generation reaction and headspace extracted into 100 μL chromogenic reagent, which contains methanol as extractant and TGA-AuNPs as nanosensors, leading to aggregation of TGA-AuNPs and therefore a red-to-blue color change. Parameters influencing the chromogenic and hydride generation reactions were optimized. Addition of 300 μM ethylenediamine tetraacetic acid (EDTA) as masking agent largely suppressed the inferences from mercury and arsenic. The proposed method can tolerate at least 10-fold As(III) and 100-fold other metal ions including Hg(II). The detection limits were 6.0 and 1.2 μg/L Sb(III) by naked-eye and UV-Vis spectrometer, respectively, which meet the maximum admissible level in drinking water (6 μg/L) set by the United States Environmental Protection Agency. The feasibility of the proposed method was demonstrated by rapid detection of Sb(III) in river water, lake water, ground water and sea water samples by naked-eye at a spiking level of 6 μg/L Sb(III). [Display omitted] •Thioglycolic acid coated gold nanoparticles were evaluated as headspace nanosensors for colorimetric detection of Sb(III).•Chromogenic and hydride generation conditions were optimized to increase the method sensitivity and tolerance.•The method exhibited quite high sensitivity, and acceptable tolerance with the aid of masking agent.•The method showed high performance in detection of Sb(III) from environmental waters.•This study is the first report on Sb(III) colorimetric detection on the basis of using nanosensors as chromophores.