title: Dithiocarbamate-capped silver nanoparticles as a resonance light scattering probe for simultaneous detection of lead(II) ions and cysteine.
abstract: We investigated the suitability of dithiocarbamate (DTC) capped Ag nanoparticles (NPs) as resonance light scattering (RLS) probes for the simultaneous sensing of Pb(2+) and cysteine. The DTC capping ligands are generated by a very simple in situ method through reaction of carbon disulfide with diethanolamine as primary precursor molecules under ultrasonic irradiation. This strategy was based on the fact that Pb(2+) could induce the aggregation of DTC-Ag NPs due to the strong metal affinity of DTC along with an enhanced RLS signal. After optimizing some experimental conditions (including the pH value of the solution, concentration of DTC-Ag NPs, and ion strength), a very simple and facile sensing system has been developed for the detection of Pb(2+) in water based on RLS technology. The proposed system promises excellent selectivity, a wide linear response range and high sensitivity for Pb(2+). The linear response range for Pb(2+) was from 0.01 μM to 60 μM. The limit of detection (S/N = 3σ) for Pb(2+) was as low as 4 nM. The proposed method was successfully used to detect Pb(2+) in river and tap water samples, indicating the potential of this new, sensitive and selective method in water quality monitoring. Meanwhile, due to the strong binding preference of cysteine toward Pb(2+) by the formation of Pb(2+)-S bonds, Pb(2+) was removed from the surfaces of the DTC-Ag NPs, leading to redispersion of DTC-Ag NPs, along with a decreased RLS signal. The possibility of the proposed system for the sensing of cysteine was also investigated.
authors: State Key Laboratory Breeding Base of Eco-Environments and Bio-Resources of the Three Gorges Reservoir Region, College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, China.
authors: Haiyan
authors: H
authors: Cao
authors: Minghong
authors: M
authors: Wei
authors: Zhaohui
authors: Z
authors: Chen
authors: Yuming
authors: Y
authors: Huang
mesh_terms: D002246:Carbon Disulfide / Q000737:chemistry; D003124:Colorimetry; D003545:Cysteine / Q000032:analysis*; D060766:Drinking Water / Q000032:analysis / Q000737:chemistry; D004983:Ethanolamines / Q000737:chemistry; D007854:Lead / Q000032:analysis*; D057230:Limit of Detection; D053768:Metal Nanoparticles / Q000737:chemistry*; D045483:Rivers / Q000737:chemistry; D012834:Silver / Q000737:chemistry*; D013859:Thiocarbamates / Q000737:chemistry*; D060753:Water Quality
chemical_list: D060766:Drinking Water; D004983:Ethanolamines; D013859:Thiocarbamates; D007854:Lead; D012834:Silver; C020283:diethanolamine; D003545:Cysteine; D002246:Carbon Disulfide