International Journal of Analytical Chemistry

Review Article

Recent Studies on the Speciation and Determination of Mercury in Different Environmental Matrices Using Various Analytical Techniques

Table 2

Analytical parameters of reviewed research papers involving speciation and determination of mercury by electrochemical instruments.


Analyte	Method	Supporting media	Analytical instrument	LOD	Linearity range	QA/QC studies	Analyzed samples	Interference study	Ref

Hg(II)	Biosensor	Y-shaped DNA	Square wave voltammeter	0.094 nM	1 nM–5 μM	Selectivity, sensitivity, and repeatability were studied	River water samples	Interferences of Cu²⁺, Al³⁺, Co²⁺, Fe3⁺, Zn²⁺, Ni²⁺, Cd²⁺, Ba²⁺, Cr³⁺, Mg²⁺, and Pb²⁺ were reported	[121]

Hg(II)	Preconcentration	N-Octylpyridinium	Stripping voltammeter	0.0015 μM	0–0.5 μM	The RSD of the method was 10%	Tap, pond, and wastewaters	No significant interference of 100 μg L⁻¹ of Cu²⁺, Pb²⁺, Cd²⁺, and Zn²⁺ was observed in the determination of Hg²⁺	[122]

Hg(II)	Electrochemical	Screen printed carbon electrode	Anodic stripping voltammeter	0.005 μM	0.005–0.5 μM	Accuracy of the method was evaluated with ICP/MS	Groundwater	Interference of Cu²⁺, Co²⁺, Fe²⁺, Zn²⁺, Ni²⁺, Cd²⁺, Mn²⁺, Mg²⁺, and Pb²⁺ was negligible in the determination of Hg²⁺	[123]

Hg(II)	Electrochemical sensor	1-(2, 4-Dinitrophenyl)-dodecanoyl thiourea	Cyclic, square wave and differential pulse voltammeter	0.0032 μM	Up to 0.01 μM	The RSD of the method was 3.5%	Drinking and tap water samples	5-fold Cu²⁺, Cd²⁺, Pb²⁺, and Zn²⁺ did not interfere in the determination of Hg(II)	[124]

Hg(II)	Electrochemical	N-PC-Au	Anodic stripping voltammeter	0.35 nM	0.001–1 μM	—	Drinking water	The electrode was not affected by the presence of Zn²⁺, Pb²⁺, Cu²⁺, and Cd²⁺ ions in the determination of Hg(II)	[79]

Hg(II)	Electrochemical sensor	Modified gold nanoparticles	Cyclic voltammeter	7.5 μM	5.0–50 μM	—	Spiked water samples	The method is selective towards the presence of Zn²⁺, Cd²⁺, Pb²⁺, Cu²⁺, Ni²⁺, and Co²⁺ ions	[80]

Hg(II)	Electrochemical	N-doped graphene electrode	Differential pulse voltammeter	0.05 μM	0.2–9 μM	The RSD of Hg determination with six repetitions was 2.1%		Simultaneously Cd²⁺, Cu²⁺, and Pb²⁺ were determined along with Hg²⁺	[99]

Hg(II)	Electrochemical sensor	Screen printed carbon electrode	Differential pulse anodic stripping voltammeter	0.0001 μM	0.0002–0.01 μM	Recovery of Hg(II) was found as 106%	Real water samples	High tolerance limits were observed for Fe³⁺, Zn²⁺, and Cd²⁺ but lower tolerance limits for Pb²⁺ and Cu²⁺ were found	[125]

Hg(II)	Electrochemical sensor	DNA probe	Cyclic and square wave voltammeter	5.6 nM	10–100 nM	—	—	10-fold Pb²⁺, Mn²⁺, Zn²⁺, Ni²⁺, Cu²⁺, Fe²⁺, Ba²⁺, and Cd²⁺ did not interfere in the determination of Hg(II)	[81]

Hg(II)	Electrochemical	Carbon ionic liquid paste electrode	Anodic stripping voltammeter	0.1 nM	0.5–10 nM and 0.08–2 μM	—	Wastewater samples	Over 30-fold Zn2+, Cr3+, and Pb2+ and over 45-fold Cd2+, Cu2+, Ni2+, and Mn2+ interfered in the determination of Hg(II)	[82]

Hg(II)	Electrochemical	Carbon paste sensor	Potentiometer	1.95 × 10⁻⁹M	4.00 × 10⁻⁹–1.30 × 10⁻³M	Reproducibility of the method was reported	Water samples	Selective coefficients of various cations for Hg(II) selective sensors were reported	[126]

Hg(II)	Biosensor	Thymine	Differential pulse and cyclic voltammeter	0.08 nM	0.5–5000 nM	Recoveries of Hg(II) in real samples were in the range of 96.4–103%	Water and human serum	Selective in presence of Al³⁺, Ba²⁺, Cd²⁺, Co²⁺, Cr³⁺, Fe³⁺, Mn²⁺, Pb²⁺, and Zn²⁺	[127]

Hg(II)	Biosensor	Cyclic dithiothreitol	Cyclic voltammeter	28 pM	0.1 nM–5 μM	Recoveries of Hg(II) in water samples were in the range of 98.8–104%	River water samples	Excellent selectivity for Hg(II) detection was observed in presence of Cd²⁺, Pd²⁺, and Co²⁺	[128]

Hg(II)	Biosensor	Methylene blue	Cyclic voltammeter	8.7 × 10⁻¹¹M	1.0 × 10⁻¹⁰–5.0 × 10⁻⁷ M	The RSD of the sensor was 5.25% for 10 replicates indicating the good reproducibility	Tap and river water samples	Cd²⁺, Ba²⁺, Pb²⁺, Ni²⁺, Cu²⁺, Zn²⁺, Mn²⁺, Ca²⁺, Co²⁺, Mg²⁺, and Ag⁺ did not interfere up to 250 nM in presence of 50 nM of Hg(II)	[129]

Hg(II)	Electrochemical	PVC membrane sensor	Potentiometer	3.2 × 10⁻⁹ M	1.0 × 10⁻⁸–5.0 × 10⁻³M	RSD values for synthetic samples measurements were less than 3.10%	Wastewater samples	The selectivity coefficients for various ions were in the range of 1.0 × 10⁻⁴–4.5 × 10⁻⁴ M	[130]

Hg(II)	Electrochemical	Copper film electrode	Anodic stripping voltammeter	0.0005 μM	0.05–0.5 μM	The RSD value for 12 replicates of Hg determination was 4.5%	—	Simultaneously mercury and lead are determined	[100]

Hg(II)	Electrochemical	Carbon nanotubes	Anodic stripping voltammeter	0.025 μM	0.1–100 μM	The RSD value for six replicates was 1.93%	River and industrial wastewater	Up to 200-fold Pb²⁺, Cu²⁺, Cd²⁺, Zn²⁺, Ni²⁺, and Mn²⁺ did not interfere in the determination of Hg(II)	[131]

Hg(II)	Electrochemical sensor	Mesoporous carbon nanofibre	Anodic stripping voltammeter	0.3 nM	5–500 nM	The RSD values in the determination of Hg(II) in real samples were less than 2.3%	Yellow river, China	The proposed electrode avoids the interferences of Cd²⁺, Pb²⁺, and Cu²⁺	[132]

Hg(II)	Potentiometric sensor	MWCNTs	Potentiometer	3.1 × 10⁻⁹M	4.0 × 10⁻⁹–2.2 × 10⁻³ M	The recoveries of Hg(II) were in the range of 99–102%	Aqueous samples	The proposed method was highly selective towards the determination of Hg(II) in presence of some other interfering ions in aqueous samples	[133]

Hg(II)	Electrochemical	Rotating silver electrode	Square wave voltammeter	4.61 × 10⁻⁸M	1.0 × 10⁻⁷–8.0 × 10⁻⁴ M	The RSD for seven replicates was 2.19%	Milk and breast milk	No interferences of copper, cobalt, iron, and zinc were observed	[134]

Hg(II)	Electrochemical	Graphene modified with silver	Differential pulse voltammeter	3.38 × 10⁻⁸M	5.0 × 10⁻⁸–1.0 × 10⁻⁴M	The RSD for eight replicates was 2.25%	Leachate samples	Even 200 times excess of Al³⁺, Cd²⁺, Co²⁺, Ni²⁺, Pb²⁺, Fe²⁺, Fe³⁺, and Zn²⁺ did not interfere	[135]

Hg(II)	Electrochemical	Graphene oxide	Cyclic voltammeter	0.035 nM	0.1–100 nM	The RSD value in the reproducible test was 4.5%	River water samples	Even 10 times higher concentrations of Co²⁺, Mn²⁺, Pb²⁺, and Fe³⁺ did not interfere in the determination of Hg(II)	[136]

Hg(II)	Electrochemical	Gold nanoparticles	Differential pulse anodic stripping voltammeter	0.0001 μM	0.0005–0.05 μM	Recoveries of Hg(II) in real samples were in the range of 87–102%	Tap and lake waters, milk, and soils	1000-fold Zn²⁺, Cd²⁺, Pb²⁺, Mn²⁺, Co²⁺, and Cu²⁺ did not interfere in the determination of Hg(II)	[137]

Hg(II)	Electrochemical	Gold nanoparticles	Stripping voltammeter	1 μM	—		Water samples	—	[83]

Hg(II)	Electrochemical	Graphene-Au modified electrode	Square wave voltammeter	0.001 aM	1.0 aM–100 nM	The RSD values for triplicate measurements was less than 4.46%	Spiked tap and river waters and landfill leachate samples	Even 500 nM of Cd²⁺, Co²⁺, Cr²⁺, Cu²⁺, Mn²⁺, Ni²⁺, Pb²⁺, Zn²⁺, Al³⁺, and Fe³⁺ did not interfere in the determination of 10 nM of Hg(II)	[48]

Hg(II)	Electrochemical	Graphene/CeO₂	Differential pulse anodic stripping voltammeter	2.187 × 10⁻¹¹ M	0.002–0.12 μM	—	Wastewaters	Simultaneously Cd²⁺, Pb²⁺, Cu²⁺, and Hg²⁺ were determined	[84]

Hg(II)	Electrochemical	Graphene quantum dots	Anodic stripping voltammeter	0.02 nM	0.02–1.5 nM	Recoveries from spiked samples were in the range of 96.6–101%	Spiked samples	Cu²⁺ was also determined along with Hg(II)	[138]

Total Hg	Liquid-liquid microextraction	Screen printed carbon electrodes	Square wave anodic stripping voltammeter	0.00005 μM	0.0025–0.05 μM	The recoveries in the determination of mercury in real samples were in the range of 95–108%	Tap, river, and bottled and industrial wastewaters	—	[139]

Total Hg	Electrochemical sensing	Zinc oxide quantum dots	Linear sweep voltammeter	0.005 μl/L	0.005–0.05 μl/L	—	River and groundwater	Except Cd²⁺, the other ions, such as Zn²⁺, Pb²⁺, and As³⁺ did not interfere	[85]

Total Hg	Electrochemical	Gold nanoparticles	Quartz crystal microbalance	0.15 nM	3–300 nM	The results were compared with CV-AAS technique. The RSD was found to be less than 7%	Water and sediment samples	Interference of Cu²⁺, Cr³⁺, Pb²⁺, and Cd²⁺ was reported	[140]

Hg(0)	Electrochemical	Gold-based microsensor	Quartz crystal microbalance	—	—	The results were accurate and within 8% of the concentrations reported by EPA certified samples	Industrial flue gas	—	[141]

Hg(0)	Electromechanical	—	Quartz crystal microbalance	2.42 × 10⁻⁸ μM	—	Selectivity of the instruments for mercury was 84%	—	—	[142]

Hg(0)	Electrochemical	Silver/gold core/shell nanowire monolayer	Quartz crystal microbalance	0.039 μM	—	Repeatability of the results was always greater than 87%	Industrial gas effluents	—	[143]

N-PC-Au: nitrogen-doped porous carbon-gold nanocomposite; MWCNTs: multiwalled carbon nanotubes.