SERS scaffold based on silver nanoparticles with multi-ingredient heavy metal ligands for the determination of Mn(II).

Heavy metal ions are difficult to determine directly by surface-enhanced Raman spectroscopy (SERS) due to the lack of Raman characteristic peaks for heavy metal. Herein, a SERS platform was promoted for the determination of divalent manganese ion (Mn2+) with the properties of cost-effectiveness and simplicity. The SERS platform was constructed into a hybrid system of silver nanoparticles (AgNPs), 6-mercaptonicotinic acid (MNA), and melamine (MA). The likely principle of the SERS analysis platform for Mn2+ is that 6-mercaptonic acid cooperates with melamine to combine manganese ions to cause the aggregation of silver nanoparticles, resulting in the rapid enhancement of Raman characteristic peak signals of 6-mercaptonic acid. The established SERS platform for the Mn2+ determination obtained good linearity in the range of Mn2+ concentration of 1.0 × 10−5–1.0 × 10−4 mol/L with a limit of detection (LOD) of 4.0 × 10−6 mol/L. [ABSTRACT FROM AUTHOR]