title: Direct, reagentless electrochemical detection of the BIR3 domain of X-linked inhibitor of apoptosis protein using a peptide-based conducting polymer sensor.
abstract: In this work, we report a reagentless electrochemical peptide (AVPFAQKG) sensor to directly detect the BIR3 domain of X-linked inhibitor of apoptosis protein (XIAP-BIR3). The bioreceptor was based on a conducting copolymer film electrosynthesized from juglone and a juglone-peptide conjugate (JP) newly designed. The peptide-protein interactions generated an important increase of steric hindrance at the interface and a current decrease (signal off) of the redox reaction from quinone embedded in the polymer backbone as evidenced by Square Wave Voltammetry. This allowed a specific and sensitive detection of XIAP-BIR3 with a detection limit of 1 nM (13 ng mL(-1)). The peptide-protein complex could be then dissociated by adding the free precursor peptide (AVPFAQKG) into solution, causing a shift-back on the signal, i.e. an increase in the current intensity (signal-on). This "off-on" detection sequence was used in this work as a double verification of the specificity and this approach can be employed as a general way to increase the reliability of the results. In general, the approach described in this work may be inspired to develop other direct and reagentless electrochemical protein assays with high specificity and sensitivity.
authors.affiliation: Lanzhou University, School of Nuclear Science and Technology, Lanzhou 730000, China; University Paris Diderot, Sorbonne Paris Cité, ITODYS, UMR CNRS 7086, 15 rue J-A de Baïf, 75205 Paris Cedex 13, France.
authors.forename: X
authors.initials: X
authors.lastname: Wang
authors.affiliation: University Paris Diderot, Sorbonne Paris Cité, ITODYS, UMR CNRS 7086, 15 rue J-A de Baïf, 75205 Paris Cedex 13, France. Electronic address: piro@univ-paris-diderot.fr.
authors.forename: B
authors.initials: B
authors.lastname: Piro
authors.affiliation: University Paris Diderot, Sorbonne Paris Cité, ITODYS, UMR CNRS 7086, 15 rue J-A de Baïf, 75205 Paris Cedex 13, France.
authors.forename: S
authors.initials: S
authors.lastname: Reisberg
authors.affiliation: University Paris Diderot, Sorbonne Paris Cité, ITODYS, UMR CNRS 7086, 15 rue J-A de Baïf, 75205 Paris Cedex 13, France.
authors.forename: G
authors.initials: G
authors.lastname: Anquetin
authors.affiliation: Université de Strasbourg, UMR CNRS 7213, Laboratoire de Biophotonique et Pharmacologie, Faculté de Pharmacie, 67401 Illkirch, France.
authors.forename: H
authors.initials: H
authors.lastname: de Rocquigny
authors.affiliation: Lanzhou University, Institute of Cancer Biology and Drug Screening, School of Life Sciences, Lanzhou 730000, China.
authors.forename: P
authors.initials: P
authors.lastname: Jiang
authors.affiliation: Lanzhou University, Institute of Cancer Biology and Drug Screening, School of Life Sciences, Lanzhou 730000, China.
authors.forename: Q
authors.initials: Q
authors.lastname: Wang
authors.affiliation: Lanzhou University, School of Nuclear Science and Technology, Lanzhou 730000, China.
authors.forename: W
authors.initials: W
authors.lastname: Wu
authors.affiliation: University Paris Diderot, Sorbonne Paris Cité, ITODYS, UMR CNRS 7086, 15 rue J-A de Baïf, 75205 Paris Cedex 13, France.
authors.forename: M-C
authors.initials: MC
authors.lastname: Pham
authors.affiliation: University Paris Diderot, Sorbonne Paris Cité, ITODYS, UMR CNRS 7086, 15 rue J-A de Baïf, 75205 Paris Cedex 13, France; Institute for Interdisciplinary Research, Jianghan University, Wuhan Economic and Technological Development Zone, Wuhan 430056, China. Electronic address: dong@univ-paris-diderot.fr.
authors.forename: C-Z
authors.initials: CZ
authors.lastname: Dong
mesh_terms: D000595:Amino Acid Sequence; D015374:Biosensing Techniques / Q000295:instrumentation*; D055664:Electrochemical Techniques / Q000295:instrumentation*; D004867:Equipment Design; D057230:Limit of Detection; D008958:Models, Molecular; D009285:Naphthoquinones / Q000737:chemistry* / Q000378:metabolism; D009842:Oligopeptides / Q000737:chemistry* / Q000378:metabolism; D017434:Protein Structure, Tertiary; D015203:Reproducibility of Results; D051636:X-Linked Inhibitor of Apoptosis Protein / Q000032:analysis* / Q000378:metabolism
chemical_list: D009285:Naphthoquinones; D009842:Oligopeptides; D051636:X-Linked Inhibitor of Apoptosis Protein; C005134:juglone
keywords: Electrochemical peptide sensor; Protein biomarker; Reagentless detection; Signal-off/signal-on; XIAP-BIR3