Table 2:

Comparison of limit of detection of mercuric ion

Method	Limit of detection	Reference
Colorimetric	100 nM	[8]
Colorimetric	0.19 μM	[38]
Colorimetric	2 μM	[39]
Rayleigh Scattering	0.4 nM	[20]
Electrochemical	0.5 nM	[40]
Electrochemical	10 nM	[13]
Fluorescence	121 nM	[41]
Fluorescence	3.3 nM	[42]
Fluorescence	0.3 nM	[22]
Fluorescence	0.18 nM	[19]
Upconversion	0.14 nM	This study