title: [Study on adsorption of nonpolar R-side amino acids on silver nanoparticles by FT-SERS].
abstract: The adsorption orientation and adsorption characteristics of aliphatic-nonpolar amino acids represented by L-methionine on silver nanoparticles were studied by FT-surface-enhanced Raman spectroscopy (FT-SERS) method with different pH and concentrations. According to the experiments, in order to get the best FT-SERS effects, the optimal concentration range of the L-methionine on silver sol is between 10(-3) mol x L(-1)-10(-4)(mol x L(-1). The FT-SERS effects and adsorption model change with pH; The SERS are poor when pH is near the isoelectric point or over 11 or 3. The interaction of L-methionine with Ag nanoparticles is the physical and chemical adsorption by NH3, COO-, S, which could also be effected by pH. From the results and previous reports on this aspect, the general rules of the adsorption model and the orientation of the aliphatic-nonpolar amino acids on silver nanoparticles were speculated, which would be useful for the study of amino acids, protein, peptide, enzyme etc.
authors.affiliation: Southwest University, School of Chemistry and Chemical Engineering, Chongqing 400715, China.
authors.forename: Si
authors.initials: S
authors.lastname: Li
authors.forename: Guang-Ming
authors.initials: GM
authors.lastname: Zhou
authors.forename: Da-Cheng
authors.initials: DC
authors.lastname: Yang
authors.forename: Dan-Ni
authors.initials: DN
authors.lastname: Yu
authors.forename: Hong-Jun
authors.initials: HJ
authors.lastname: Peng
authors.forename: Xin-Jun
authors.initials: XJ
authors.lastname: Wu
authors.forename: Ning
authors.initials: N
authors.lastname: Wang
mesh_terms: D000327:Adsorption; D000596:Amino Acids / Q000032:analysis*; D006863:Hydrogen-Ion Concentration; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D046529:Microscopy, Electron, Transmission; D012834:Silver / Q000737:chemistry*; D013059:Spectrum Analysis, Raman / Q000379:methods*
chemical_list: D000596:Amino Acids; D012834:Silver