Detection of Hg²⁺ Metal Ions Using Silver Nanoparticles Stabilized by Gelatin and Tween-20

Silver nanoparticles were synthesized by reduction method using glucose as reducing agent for precursor AgNO 3 . This research was aimed at comparing the stability and performance of silver nanoparticles with stabilizer gelatin (Gelatin-AgNPs) and tween-20 (Tween-AgNPs) produced from the synthesis to the silver nanoparticles without stabilizer, and applying the Gelatin-AgNPs and Tween-AgNPs to detect heavy metal in water sample. The silver nanoparticles produced were characterized using UV-Vis spectrophotometer and Transmission Electron Microscopy (TEM). From measurement of UV-Vis spectrophotometer, the absorbance wavelength of silver nanoparticles (AgNPs) appeared in range 411 nm, Gelatin-AgNPs in 417 nm, and Tween-AgNPs in 420 nm. The identification using TEM showed the average size for each AgNPs, Gelatin-AgNPs, and Tween-AgNPs was 11.73, 9.68, and 17.54 nm, respectively. The result showed that Gelatin-AgNPs has better stability compared to Tween-AgNPs. The reaction of Gelatin-AgNPs and Tween-AgNPs with several ions showed color changes of Gelatin-AgNPs and Tween-AgNPs occurred only on addition to Hg 2+ metal ions solution. Based on the experiment of Hg 2+ metal ions determination this method has limit of detection of 0.45 mg/L for Gelatin-AgNPs and 0.13 mg/L for Tween-AgNPs.