Synthesis of Starch-Stabilized Ag Nanoparticles and Hg2+Recognition in Aqueous Media
1 School of Chemistry and Chemical Engineering, Shandong University, 250100, Jinan, People’s Republic of China
2 School of Chemistry and Chemical Engineering, University of Jinan, 250022, Jinan, People’s Republic of China
Nanoscale Research Letters 2009, 4:1230-1235 doi:10.1007/s11671-009-9387-6Published: 15 July 2009
The starch-stabilized Ag nanoparticles were successfully synthesized via a reduction approach and characterized with SPR UV/Vis spectroscopy, TEM, and HRTEM. By utilizing the redox reaction between Ag nanoparticles and Hg2+, and the resulted decrease in UV/Vis signal, we develop a colorimetric method for detection of Hg2+ion. A linear relationship stands between the absorbance intensity of the Ag nanoparticles and the concentration of Hg2+ion over the range from 10 ppb to 1 ppm at the absorption of 390 nm. The detection limit for Hg2+ions in homogeneous aqueous solutions is estimated to be ~5 ppb. This system shows excellent selectivity for Hg2+over other metal ions including Na+, K+, Ba2+, Mg2+, Ca2+, Fe3+, and Cd2+. The results shown herein have potential implications in the development of new colorimetric sensors for easy and selective detection and monitoring of mercuric ions in aqueous solutions.