title: Conjugation of luminescent quantum dots with antibodies using an engineered adaptor protein to provide new reagents for fluoroimmunoassays.
abstract: We describe the preparation and characterization of bioinorganic conjugates made with highly luminescent semiconductor CdSe-ZnS core-shell quantum dots (QDs) and antibodies for use in fluoroimmunoassays. The conjugation strategy employs an engineered molecular adaptor protein, attached to the QDs via electrostatic/hydrophobic self-assembly, to link the inorganic fluorophore with antibodies. In this method, the number of antibodies conjugated to a single QD can be varied. In addition, we have developed a simple purification strategy based on mixed-composition conjugates of the molecular adaptor and a second two-domain protein that allows the use of affinity chromatography. QD-antibody conjugates were successfully used in fluoroimmunoassays for detection of both a protein toxin (staphylococcal enterotoxin B) and a small molecule (2,4,6-trinitrotoluene).
authors.affiliation: Center for Bio/Molecular Science and Engineering and Division of Optical Sciences, U.S. Naval Research Laboratory, Washington, DC 20375, USA. erg@cbmse.nrl.navy.mil
authors.forename: Ellen R
authors.initials: ER
authors.lastname: Goldman
authors.forename: George P
authors.initials: GP
authors.lastname: Anderson
authors.forename: Phan T
authors.initials: PT
authors.lastname: Tran
authors.forename: Hedi
authors.initials: H
authors.lastname: Mattoussi
authors.forename: Paul T
authors.initials: PT
authors.lastname: Charles
authors.forename: J Matthew
authors.initials: JM
authors.lastname: Mauro
mesh_terms: D000595:Amino Acid Sequence; D000906:Antibodies / Q000737:chemistry*; D005455:Fluorescent Antibody Technique; D005470:Fluorometry; D007074:Immunoglobulin G / Q000737:chemistry; D007202:Indicators and Reagents; D008163:Luminescent Measurements; D008969:Molecular Sequence Data; D015202:Protein Engineering / Q000379:methods*; D014303:Trinitrotoluene / Q000737:chemistry
chemical_list: D000906:Antibodies; D007074:Immunoglobulin G; D007202:Indicators and Reagents; D014303:Trinitrotoluene