title: Colorimetric detection of Mn2+ using silver nanoparticles cofunctionalized with 4-mercaptobenzoic acid and melamine as a probe.
abstract: A facile, selective and highly sensitive method is proposed for colorimetric detection of manganese ions using 4-mercaptobenzoic acid (4-MBA) and melamine (MA) modified silver nanoparticles (AgNPs). The presence of Mn(2+) induces the aggregation of AgNPs through cooperative metal-ligand interaction, resulting in a color change from bright yellow to purple. The cofunctionalized AgNPs showed obvious advantages over the ones functionalized only by 4-MBA or MA in terms of selectivity. Mn(2+) could be monitored by colorimetric response of AgNPs by a UV-vis spectrophotometer or even naked eyes. The absorbance ratio (A(550 nm)/A(408 nm)) is linear with the concentration of Mn(2+) ranging from 5×10(-7) mol/L to 1×10(-5) mol/L with a correlation coefficient of 0.993, and the detection limit is as low as 5×10(-8) mol/L. Particularly, this cost-effective process also allowed rapid and simple determination of the Mn(2+) in drinking water.
authors: College of Chemistry and Chemical Engineering, Graduate University of Chinese Academy of Sciences, 19A YuQuan Road, Beijing 100049, China.
authors: Ying
authors: Y
authors: Zhou
authors: Hong
authors: H
authors: Zhao
authors: Chang
authors: C
authors: Li
authors: Peng
authors: P
authors: He
authors: Wenbo
authors: W
authors: Peng
authors: Longfei
authors: L
authors: Yuan
authors: Lixi
authors: L
authors: Zeng
authors: Yujian
authors: Y
authors: He