title: Direct conjugation of antibodies to the ZnS shell of quantum dots for FRET immunoassays with low picomolar detection limits.
abstract: Compact and functional nanoparticle-antibody conjugates are of paramount importance for the development of quantum dot (QD)-based immunoassays. Here, we present a simple strategy to directly conjugate IgG, F(ab')2, and Fab antibodies via their endogenous disulfide groups directly to the inorganic ZnS shell of compact penicillamine-coated QDs. The functionality of the conjugates was demonstrated by terbium (Tb)-to-QD FRET immunoassays against prostate specific antigen in serum samples. Detection limits of 2.5 pM (0.080 ng mL-1) were 10 and 25 times lower compared to conjugation via maleimide-terminated ligands and polymer chains, respectively. These more compact, simple, and sensitive QD-antibody conjugates will be highly advantageous for nanocrystal-based biosensing applications.
authors.affiliation: NanoBioPhotonics (nanofret.com), Institute for Integrative Biology of the Cell (I2BC), Université Paris-Saclay, Université Paris-Sud, CNRS, CEA, 91405 Orsay Cedex, France. niko.hildebrandt@u-psud.fr.
authors.forename: S
authors.initials: S
authors.lastname: Bhuckory
authors.affiliation: Univ. Grenoble Alpes, INAC-SyMMES, 38054 Grenoble Cedex 9, France and CEA, INAC-SyMMES, Laboratoire STEP, 38054 Grenoble Cedex 9, France. peter.reiss@cea.fr and CNRS, SPrAM, 38054 Grenoble Cedex 9, France.
authors.forename: L
authors.initials: L
authors.lastname: Mattera
authors.affiliation: NanoBioPhotonics (nanofret.com), Institute for Integrative Biology of the Cell (I2BC), Université Paris-Saclay, Université Paris-Sud, CNRS, CEA, 91405 Orsay Cedex, France. niko.hildebrandt@u-psud.fr and CEA, INAC-SyMMES, Laboratoire STEP, 38054 Grenoble Cedex 9, France. peter.reiss@cea.fr.
authors.forename: K D
authors.initials: KD
authors.lastname: Wegner
authors.affiliation: NanoBioPhotonics (nanofret.com), Institute for Integrative Biology of the Cell (I2BC), Université Paris-Saclay, Université Paris-Sud, CNRS, CEA, 91405 Orsay Cedex, France. niko.hildebrandt@u-psud.fr.
authors.forename: X
authors.initials: X
authors.lastname: Qiu
authors.affiliation: NanoBioPhotonics (nanofret.com), Institute for Integrative Biology of the Cell (I2BC), Université Paris-Saclay, Université Paris-Sud, CNRS, CEA, 91405 Orsay Cedex, France. niko.hildebrandt@u-psud.fr.
authors.forename: Y-T
authors.initials: YT
authors.lastname: Wu
authors.affiliation: Institut Pluridisciplinaire Hubert Curien (IPHC), UMR 7178 CNRS/Université de Strasbourg, Laboratoire d'Ingénierie Moléculaire Appliquée à l'Analyse (LIMAA), ECPM, 67087 Strasbourg Cedex 2, France.
authors.forename: L J
authors.initials: LJ
authors.lastname: Charbonnière
authors.affiliation: Univ. Grenoble Alpes, INAC-SyMMES, 38054 Grenoble Cedex 9, France and CEA, INAC-SyMMES, Laboratoire STEP, 38054 Grenoble Cedex 9, France. peter.reiss@cea.fr and CNRS, SPrAM, 38054 Grenoble Cedex 9, France.
authors.forename: P
authors.initials: P
authors.lastname: Reiss
authors.affiliation: NanoBioPhotonics (nanofret.com), Institute for Integrative Biology of the Cell (I2BC), Université Paris-Saclay, Université Paris-Sud, CNRS, CEA, 91405 Orsay Cedex, France. niko.hildebrandt@u-psud.fr.
authors.forename: N
authors.identifier: http://orcid.org/0000-0001-8767-9623
authors.initials: N
authors.lastname: Hildebrandt