Flow Injection Photochemical Vapor Generation Coupled with Miniaturized Solution-Cathode Glow Discharge Atomic Emission Spectrometry for Determination and Speciation Analysis of Mercury

Abstract

A novel, compact, and green method was developed for the determination and speciation analysis of mercury, based on flow injection photochemical vapor generation (PVG) coupled with miniaturized solution cathode glow discharge-atomic emission spectroscopy (SCGD-AES). The SCGD was generated between a miniature hollow titanium tube and a solution emerging from a glass capillary. Cold mercury vapor (Hg(0)) was generated by PVG and subsequently delivered to the SCGD for excitation, and finally the emission signals were recorded by a miniaturized spectrograph. The detection limits (DLs) of Hg(II) and methylmercury (MeHg) were both determined to be 0.2 μg L. Moreover, mercury speciation analysis could also be performed by using different wavelengths and powers from the UV lamp and irradiation times. Both Hg(II) and MeHg can be converted to Hg(0) for the determination of total mercury (T-Hg) with 8 W/254 nm UV lamp and 60 s irradiation time; while only Hg(II) can be reduced to Hg(0) and determined selectively with 4 W/365 nm UV lamp and 20 s irradiation time. Then, the concentration of MeHg can be calculated by subtracting the Hg(II) from the T-Hg. Because of its similar sensitivity and DL at 8 W/254 nm, the simpler and less toxic Hg(II) was used successfully as a primary standard for the quantification of T-Hg. The novel PVG-SCGD-AES system provides not only a 365-fold improvement in the DL for Hg(II) but also a nonchromatographic method for the speciation analysis of mercury. After validating its accuracy, this method was successfully used for mercury speciation analysis of water and biological samples.

Speciation Analysis of Trace Arsenic, Mercury, Selenium and Antimony in Environmental and Biological Samples Based on Hyphenated Techniques

“…Although there are some reports on the analysis of As, Hg, Se and Sb species by AAS [164,165,166,167] or AES [168,169,170] in recent years, AFS is described to be superior to AAS and similar to ICP-MS regarding sensitivity and linear calibration range for As and Se species in routine analysis. Analytical features such as low detection limits and wide linear calibration ranges, simplicity, lower acquisition and running costs make AFS a suitable atomic detector in speciation studies.…”

l‐Cysteine modified silver nanoparticles‐based colorimetric sensing for the sensitive determination of Hg2+ in aqueous solutions

“…Given the pressing demand for Hg 2+ detection, at present some traditional methods such as atomic absorption spectrophotometry (AAS), [ 10 ] atomic fluorescence spectroscopy (AFS), [ 11 ] atomic emission spectroscopy (AES), [ 12 ] high‐performance liquid chromatography (HPLC), [ 13 ] and inductively coupled plasma mass spectrometry (ICP‐MS) [ 14 ] have been used. However, shortcomings such as long, time‐consuming, and complicated operational protocols and the use of expensive equipment have limited their extensive application.…”

Advances in the Determination of Xenobiotics in Foods

“…An innovator compact method based on flow injection photochemical vapor generation (PVG) coupled with miniaturized solution cathode glow discharge atomic emission spectroscopy (SCGD-AES) was developed for the determination of Hg and its species [82]. This novel method combines the small size, independence of compressed gases and low power consumption of SCGD-AES with the simplicity, miniaturization feasibility and green analytical characteristic of PVG.…”

“…This pioneer PVG-SCGD-AES approach results on a 365-fold improvement in Hg(II) LOD (0.2 µg L -1 ) compared to SCGD-AES. The method was validated for water and biological samples including fish and could be extrapolated to other elements [82]. Nickel demonstrated to be an optimum enhancement reagent for the PVG efficiency of Hg(II) and MeHg.…”

“…Under optimized conditions, the addition of nickel (10 mg L −1 ) increased the signal intensity of Hg(II) and MeHg around 1.5 times compared to that without nickel ion. Separative techniques like GC and HPLC could be potentially combined to PVG-SCGD-AES, opening new possibilities for Hg speciation analysis [82].…”