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Updated: Feb 27, 2026

An Anaerobic Biosensor Assay for the Detection of Mercury and Cadmium
Published on: December 17, 2018
Colorimetric Detection of Mercury(II) Ion in Aqueous Solution Using Silver Nanoparticles
M Lutfi Firdaus1, Ikka Fitriani1, Santhy Wyantuti2
1Graduate School of Science Education, University of Bengkulu.
Abstract:
Novel green-chemistry synthesis of silver nanoparticles (AgNPs) is introduced as a low-cost, rapid and easy-to-use analytical method for mercury ion detection. Aqueous fruit extract of water apple (Syzygium aqueum) was used for the first time as bioreductant to synthesize stable AgNPs. The prepared AgNPs have a yellowish-brown color with a surface plasmon resonance peak at 420 nm. The addition of Hg(II) ions then changes the AgNPs color to colorless. The color change was in proportion to the concentration of Hg(II) ions. The presence of other metal ions in the system was also evaluated. The proposed method shows good selectivity and sensitivity towards Hg(II) ions. Using UV-visible spectrophotometry, the detection limit of the developed method was 8.5 × 10-7 M. The proposed method has been successfully applied for determination of Hg(II) ions in tap and lake water samples with precision better than 5%.
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