Simple and rapid colorimetric detection of Hg(II) by a paper-based device using silver nanoplates

► A simple and rapid colorimetric method for the detection of Hg(II) has been developed. ► Ag nanoplates (AgNPls) on a paper-based device have been used for the determination of Hg(II). ► The proposed pre-concentration method shows high improvement of sensitivity. ► The addition of Cu(II) to the system has been found to enhance the Hg(II) signal. ► The proposed method has been successfully employed to determine Hg(II) in real samples.