title: Microarray-based multiplexed scanometric immunoassay for protein cancer markers using gold nanoparticle probes.
abstract: We report the use of electroless gold deposition as a light scattering signal enhancer in a multiplexed, microarray-based scanometric immunoassay using gold nanoparticle probes. The use of gold development results in greater signal enhancement than the typical silver development, and multiple rounds of metal development were found to increase the resulting signal compared to one development. Using these conditions, the assay was capable of detecting 300 aM (approximately 9000 copies) of prostate specific antigen in buffer and 3 fM in 10% serum. Additionally, the highly selective detection of three protein cancer markers at low picomolar concentrations in buffer and 10% serum was demonstrated. The use of gold deposition may have significant utility in scanometric detection schemes and broader clinical and research applications.
authors.affiliation: Department of Chemistry and International Institute for Nanotechnology, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, USA.
authors.forename: Dongwoo
authors.initials: D
authors.lastname: Kim
authors.forename: Weston L
authors.initials: WL
authors.lastname: Daniel
authors.forename: Chad A
authors.initials: CA
authors.lastname: Mirkin
mesh_terms: D055910:Antibodies, Immobilized / Q000276:immunology / Q000378:metabolism; D006063:Chorionic Gonadotropin / Q000032:analysis; D006046:Gold / Q000737:chemistry*; D006801:Humans; D007118:Immunoassay / Q000379:methods*; D008297:Male; D053768:Metal Nanoparticles / Q000737:chemistry*; D017430:Prostate-Specific Antigen / Q000032:analysis / Q000097:blood; D040081:Protein Array Analysis; D011506:Proteins / Q000032:analysis*; D000509:alpha-Fetoproteins / Q000032:analysis
chemical_list: D055910:Antibodies, Immobilized; D006063:Chorionic Gonadotropin; D011506:Proteins; D000509:alpha-Fetoproteins; D006046:Gold; D017430:Prostate-Specific Antigen