A New Turn-On Fluorometric Detection Method for the Determination of Ag(I) in Some Food and Water Samples.

A new sensitive and selective turn-on fluorometry procedure for the determination of silver using a laboratory-built fluorometry system is described herein. After synthesis and characterization, a [2-((E)-{[3',6'-bis(ethylamino)-2',7'-dimethyl-3-oxospiro[isoindole-1,9'-xanthen]-2(3H)-yl]imino}methyl)cyclopenta-2,4-dien-1-yl] (cyclopenta-2,4-dien-1-yl)iron (DKMS) fluorescent reagent was used for the first time. Ag(I) was complexed with the new fluorescent reagent, and direct measurements were made using fluorometry without any separation/preconcentration. The fluorescence intensity of the Ag(I)-DKMS complex remained unchanged for over 18 h at room temperature and was a linear function of the concentration of Ag(I) in the 0-2.5 mg/L range. The optimum determination conditions were established by testing different reagent quantities, the acidity and pH of the sample, and the effect of temperature and interfering ions. The LOD of the method was 1.00 μg/L whereas the RSD was 0.1% for 0.1 mg/L Ag(I) concentration. "The developed method was applied successfully for the Ag(I) determination of silver in burn cream, anode slime, some food and water samples". Results of the analysis of Certified Reference Materials (NCS DC73349 Bush Branches and Leaves - Trace Elements, and CWW-TM-D Certified Wastewater and Trace Metals) are in good agreement with the certified values.