title: Optimizing two-color semiconductor nanocrystal immunoassays in single well microtiter plate formats.
abstract: The simultaneous detection of two analytes, chicken IgY (IgG) and Staphylococcal enterotoxin B (SEB), in the single well of a 96-well plate is demonstrated using luminescent semiconductor quantum dot nanocrystal (NC) tracers. The NC-labeled antibodies were prepared via sulfhydryl-reactive chemistry using a facile protocol that took <3 h. Dose response curves for each target were evaluated in a single immunoassay format and compared to Cy5, a fluorophore commonly used in fluorescent immunoassays, and found to be equivalent. Immunoassays were then performed in a duplex format, demonstrating multiplex detection in a single well with limits of detection equivalent to the single assay format: 9.8 ng/mL chicken IgG and 7.8 ng/mL SEB.
authors.affiliation: Division of Biology, Office of Science and Engineering Laboratories, US Food and Drug Administration, 10903 New Hampshire Avenue, Silver Spring, MD 20993, USA. kim.sapsford@fda.hhs.gov
authors.forename: Kim E
authors.initials: KE
authors.lastname: Sapsford
authors.forename: Samantha
authors.initials: S
authors.lastname: Spindel
authors.forename: Travis
authors.initials: T
authors.lastname: Jennings
authors.forename: Guoliang
authors.initials: G
authors.lastname: Tao
authors.forename: Robert C
authors.initials: RC
authors.lastname: Triulzi
authors.forename: W Russ
authors.initials: WR
authors.lastname: Algar
authors.forename: Igor L
authors.initials: IL
authors.lastname: Medintz
mesh_terms: D000818:Animals; D000906:Antibodies / Q000737:chemistry; D015374:Biosensing Techniques; D002232:Carbocyanines / Q000494:pharmacology; D002645:Chickens; D004768:Enterotoxins / Q000737:chemistry; D005455:Fluorescent Antibody Technique / Q000379:methods; D007118:Immunoassay / Q000379:methods*; D007074:Immunoglobulin G / Q000737:chemistry; D049449:Luminescence; D053758:Nanoparticles / Q000737:chemistry*; D036103:Nanotechnology / Q000379:methods; D010777:Photochemistry / Q000379:methods; D045663:Quantum Dots; D015203:Reproducibility of Results; D012666:Semiconductors
chemical_list: D000906:Antibodies; D002232:Carbocyanines; D004768:Enterotoxins; D007074:Immunoglobulin G; C085321:cyanine dye 5; C031818:enterotoxin B, staphylococcal