Surface Enhanced Raman Scattering studies of l-amino acids adsorbed on silver nanoclusters

Improved discrimination of phenylalanine enantiomers by surface enhanced Raman scattering assay: molecular insight into chiral interaction

“…1A(a), D-Phe could be detected based on the Raman peaks at 1080 (NH 2 bending), 1143 (C-C-N asymmetric stretching), 1393 (COO − symmetric stretching), 1434 (-CH 2 scissoring) and 1585 cm −1 (NH 2 vibrations). [18][19][20][21][22] As for L-Phe, the SERS spectrum (Fig. 1A(b)) of Au@Ag-L-Phe is almost the same as that of Au@Ag-D-Phe.…”

“…Moreover, the signal at 1009 cm −1 (the benzene ring breathing vibration mode of Phe) is hardly detected in Au@Ag- d -Phe (or Au@Ag- l -Phe), but is clearly observable in Au@Ag- d -Phe-Sert (or Au@Ag- l -Phe-Sert). 18 However, the enhancement effect featured enantiomeric selectivity. The enhancement degrees in d -Phe are larger than those in l -Phe at 1080 and 1585 cm −1 : ED d -1080 = 24.2 > ED l -1080 = 6.9, and ED d -1585 = 25.6 > ED l -1585 = 4.7.…”

“…Moreover, the signal at 1009 cm −1 (the benzene ring breathing vibration mode of Phe) is hardly detected in Au@Ag-D-Phe (or Au@Ag-L-Phe), but is clearly observable in Au@Ag-D-Phe-Sert (or Au@Ag-L-Phe-Sert). 18 However, the enhancement effect featured enantiomeric selectivity. The enhancement degrees in D-Phe are larger than those in It is well known that the SERS signals of molecules on the plasmonic metal surfaces depend on many factors including their concentration, conformation, polarizability, and orientation.…”

Different surface properties of l-arginine functionalized silver nanoparticles and their influence on the conductive and adhesive properties of nanosilver films

“…In the following figure, it is clear that the main bands of silver nanoparticles at 3435, 1629 cm -1 are corresponding to -NH, -NH 2 respectively. The C=O stretch peak 1562 cm -1 is disappeared and replaced by vibration of CO 2 -at 1403 cm -1 [27], which is mainly caused by the silver's attraction of electron. The appearance of CO 2 -caused a blue shift (4; 1629-1685 = -56 cm -1 ) of the -NH 2 plane bending peak.…”

Single-Molecule Electrical and Spectroscopic Profiling Protein Allostery Using a Gold Plasmonic Nanopore

“…After CaM bound Ca 2+ , a larger hydrophobic region was exposed on the surface of Ca-CaM, often followed by interaction with other biomolecules in biological processes . For instance, there were seven methionine compounds (M57, M72, M92, M93, M97, M130, and M166) located in the newly exposed region of Ca-CaM. , The peaks of 663 and 748 cm –1 were then attributed to the characteristic C–S and S–CH 3 stretching vibration of methionine. , More importantly, the multiple thioether-contained chains of methionine could offer a strong Ca–CaM–nanopore interaction via the Au–S bond. This interaction monitored by the gold plasmonic nanopore provided structural evidence to explain why the dwell time of Ca–CaM is longer than that of apo-CaM in the ion current measurement mode (Figure h,i).…”