A Rapid Surface-Enhanced Raman Scattering (SERS) Method for Pb2+ Detection Using L-Cysteine-Modified Ag-Coated Au Nanoparticles with Core–Shell Nanostructure

Abstract

A rapid surface-enhanced Raman scattering (SERS) method for Pb2+ detection has been developed based on l-cysteine-modified Ag-coated Au nanoparticles with core-shell nanostructure. Specifically, l-cysteine-functionalized Au@Ag core-shell probes bearing Raman-labeling molecules (4-ATP) are used to detect Pb2+ upon the formation of nanoparticle aggregates. The proposed SERS-based method shows a linear range between 5 pM and 10 nM, with an unprecedented limit of detection (LOD) of 1 pM for Pb2+; this LOD shows the method to be a few orders of magnitude more sensitive than the typical colorimetric approach that is based on the aggregation of noble metal nanoparticles. Real water samples diluted with pure water have been successfully analyzed. This SERS-based assay may provide a general and simple approach for the detection of other metal ions of interest, and so could have wide-ranging applications in many areas.

Synthesis and Luminescence Properties of Core-Shell-Shell Composites: SiO2@PMDA-Si-Tb@SiO2 and SiO2@PMDA-Si-Tb-phen@SiO2

“…In the last decade, core-shell composite materials, which connect different functional components that are integrated into one unit, have attracted increased attention. These materials can be used in many fields, including catalysis [ 1 , 2 , 3 , 4 , 5 , 6 , 7 ], bio-nanotechnology [ 8 , 9 , 10 , 11 ], materials chemistry [ 12 , 13 ], optical devices [ 14 , 15 , 16 , 17 , 18 ], electronics [ 19 , 20 , 21 , 22 ], and magnetic devices [ 23 , 24 , 25 , 26 , 27 ]. Among the number of core-shell composite materials [ 28 , 29 , 30 , 31 , 32 ], coating desirable compounds onto a core to form luminescence materials has emerged as one of the research hot spots in recent years.…”

Coupling of plasmonic hot spots with shurikens for superchiral SERS-based enantiomer recognition

“…The SERS spectrum is identical to that published previously for cysteine in the vicinity of Ag coated Au nanoparticles (comparative results are given in Table S1, ESI †). [48][49][50][51] The slight shift of peak position is likely due to the different excitation wavelengths and the interaction of plasmonic substrate with the cysteine via sulphur, amino and carboxylic acid groups. 50,51 In our case, however, the intensities of measured spectra are significantly affected by the enantiomers and shuriken handedness (Fig.…”

Charge Transfer Surface-Enhanced Raman and Absorption Spectra of the Zwitterionic Form of Cysteine Adsorbed on M@Au12 (M = Au, Ag, Pt, and Pd) Nanoclusters

“…41 The detection of Pb 2+ was accomplished using SERS on the LC-functionalized Au@Ag nanoparticles. 42 The SERS and DFT calculations were used to investigate the adsorption of LC on the nanoparticle surfaces. 43 Chang et al investigated the adsorption geometry of the LC on the dendric Ag surface using electrochemical methods in different pH environments.…”

“…The enhancement of the signal intensity in SERS is dependent on factors such as molecule distance, orientation, and affinity toward the metal surface. The SERS spectrum of the LC interacting with various metal surfaces has been studied both theoretically as well as experimentally. − Graff et al investigated the adsorption of the l - and d -cysteine enantiomers on an Ag electrode surface using the SERS technique as a function of electrode potential and solvent pH . A complete experimental study has been performed by Guicheteau et al on the IR, Raman, and SERS spectra of a series of amino acids (phenylalanine, tyrosine, tryptophan, glutamine, cysteine, alanine, proline, methionine, asparagine, threonine, valine, glycine, serine, leucine, isoleucine, aspartic acid, and glutamic acid) and the nucleic acid bases (adenosine, guanosine, thymidine, and uridine) .…”