Determination of Metals in Natural Waters by Inductively Coupled Plasma Optical Emission Spectroscopy after Preconcentration on Silica Sequentially Coated with Layers of Polyhexamethylene Guanidinium and Sulphonated Nitrosonaphthols

Table 7

Comparison of analytical characteristics of the preconcentration methods for determination of elements in water samples.

Adsorbent/chelating agent	Method	Element - LOD (µg L^−1)	Eluent	PF	Ref.
Amberlite XAD-4/salicylaldehyde benzoylhydrazone	FAAS	Cu(II) - 0.50, Ni(II) - 0.90,; Co(II) - 0.70, Fe(III) - 0.40	10 mL 3 M HNO3 in acetone	240	[33]
Amberlite XAD-16/p-aminobenzenesulfonic acid	FAAS	Cu(II) - 0.72, Ni(II) - 0.89,; Zn(II) - 1.05, Co(II) - 0.98,; Cr(III) - 1.17, Fe(III) - 0.69,; Pb(II) – 1.91	3-5 mL 2 M HNO3	60-100	[34]
Amberlite XAD-4/1-(2-pyridylazo)-2-naphthol	FAAS	Co(II) - 0.54, Ni(II) - 1.30,; Mn(II) - 0.20, Zn(II) - 0.28,; Pb(II) - 1.10, Cu(II) - 0.42	5 mL 2 M HClO4 for Cu(II), Ni(II); 5 mL 2 M HNO3 for Zn(II), Co(II); 2.5 mL 0.5 M H2SO4 for Cd(II), Pb(II) and Mn(II)	160-400	[35]
Chromosorb 106-TAR/4-(2-thiazolylazo) resorcinol	ICP-MS	Cu(II) - 0.012, Ni(II) - 0.0064; Pb(II) - 0.021, Zn(II) - 0.015	1 mL, 0.75 M HNO3	5	[36]
Silica/NH2	ICP-MS	Pb(II) - 0.699, Cd(II) - 0.123,; Zn(II) - 0.24	3 mL, 3M HNO3	33.3	[37]
Silica/N-(2-aminoethyl)-2,3-dihydboxybenzaldimine	ICP-OES	Cd(II) – 0.012, Cu(II) - 0.098; Ni(II) - 0.056, Pb(II) - 0.14	5 mL, 0.5 M HCl	100	[38]
Silica/sodium diethyldithiocarbamate	ICP-OES	Co(II) – 0.198, Ni(II) – 0.201	5 m, 2 MHNO3	400	[39]
GO Amberlite XAD-16/picolylamine	ICP-OES	Cu(II) – 0.048, Pb(II) – 1.43	5 mL, 2 МHCl	150	[40]
Multiwall carbon nanotubes /silica	ICP-OES	As(V) – 0.67, Cd(II) – 0.45,; Cu(II) - 0.11, Cr(III) – 0.91,; V(V) – 0.55, Zn(II) – 0.27	0.6 mL, 2 МHCl	10	[41]
SiO2-PHMG-NNS	ICP-OES	Cu(II) - 0.75, Fe(III) - 0.82,; Al(III) - 1.35, Ni(II) - 0.96,; Zn(II) - 0.77, Pb(II) - 0.88	5 mL, 1 МHNO3	28-80	This work

- for 0.5 mg of sorbent