title: Resonant Rayleigh light scattering response of individual Au nanoparticles to antigen-antibody interaction.
abstract: A proof-of-concept study was reported on analysis of antigen-antibody recognition based on resonant Rayleigh scattering response of single Au nanoparticles in an imaging chamber. As benefited by a traditional dark-field microscope and a spectrograph, individual Au nanoparticles (30 nm) were observed with high signal-to-noise ratio and they were effectively utilized to monitor changes in refractive index induced by specific binding of the adsorbates. Using PSA antigen as a model, a LSPR lambda(max) shift of about 2.85 nm was recorded for a molecular binding corresponding to 0.1 pg ml(-1) of the protein biomarker. This result successfully demonstrates a non-labeling detection system for proteins as well as thousands of different chemical or biological species, and it possesses a great potential as a sensitive, on-chip and multiplexing detection.
authors.affiliation: Nano-optics and Biomolecular Engineering National Laboratory, Department of Chemical Engineering, Sungkyunkwan University, Suwon, 440-746, Korea. simsj@skku.edu.
authors.forename: Cuong
authors.initials: C
authors.lastname: Cao
authors.forename: Sang Jun
authors.initials: SJ
authors.lastname: Sim
mesh_terms: D000906:Antibodies / Q000737:chemistry / Q000276:immunology; D000937:Antigen-Antibody Reactions; D006046:Gold / Q000032:analysis / Q000737:chemistry*; D006801:Humans; D008297:Male; D053768:Metal Nanoparticles / Q000032:analysis / Q000737:chemistry*; D008853:Microscopy / Q000379:methods; D017430:Prostate-Specific Antigen / Q000032:analysis* / Q000276:immunology*; D012680:Sensitivity and Specificity; D013438:Sulfhydryl Compounds / Q000737:chemistry; D020349:Surface Plasmon Resonance / Q000379:methods*
chemical_list: D000906:Antibodies; D013438:Sulfhydryl Compounds; D006046:Gold; D017430:Prostate-Specific Antigen