title: Active Acetylcholinesterase Immobilization on a Functionalized Silicon Surface.
abstract: In this work, we studied the attachment of active acetylcholinesterase (AChE) enzyme on a silicon substrate as a potential biomarker for the detection of organophosphorous (OP) pesticides. A multistep functionalization strategy was developed on a crystalline silicon surface: a carboxylic acid-terminated monolayer was grafted onto a hydrogen-terminated silicon surface by photochemical hydrosilylation, and then AChE was covalently attached through amide bonds using an activation EDC/NHS process. Each step of the modification was quantitatively characterized by ex-situ Fourier transform infrared spectroscopy in attenuated-total-reflection geometry (ATR-FTIR) and atomic force microscopy (AFM). The kinetics of enzyme immobilization was investigated using in situ real-time infrared spectroscopy. The enzymatic activity of immobilized acetylcholinesterase enzymes was determined with a colorimetric test. The surface concentration of active AChE was estimated to be Γ = 1.72 × 10(10) cm(-2).
authors.affiliation: ‡Unité de Recherche Matériaux et Energies Renouvelables (URMER), Département de Physique, Faculté des Sciences, Université Abou Baker Belkaid, B.P. 119, 13000 Tlemcen, Algeria.
authors.forename: K
authors.initials: K
authors.lastname: Khaldi
authors.forename: S
authors.initials: S
authors.lastname: Sam
authors.affiliation: §Physique de la Matière Condensée, Ecole Polytechnique-CNRS, 91128 Palaiseau, France.
authors.forename: A C
authors.initials: AC
authors.lastname: Gouget-Laemmel
authors.affiliation: §Physique de la Matière Condensée, Ecole Polytechnique-CNRS, 91128 Palaiseau, France.
authors.forename: C
authors.initials: C
authors.lastname: Henry de Villeneuve
authors.affiliation: §Physique de la Matière Condensée, Ecole Polytechnique-CNRS, 91128 Palaiseau, France.
authors.forename: A
authors.initials: A
authors.lastname: Moraillon
authors.affiliation: §Physique de la Matière Condensée, Ecole Polytechnique-CNRS, 91128 Palaiseau, France.
authors.forename: F
authors.initials: F
authors.lastname: Ozanam
authors.affiliation: §Physique de la Matière Condensée, Ecole Polytechnique-CNRS, 91128 Palaiseau, France.
authors.forename: J
authors.initials: J
authors.lastname: Yang
authors.affiliation: ‡Unité de Recherche Matériaux et Energies Renouvelables (URMER), Département de Physique, Faculté des Sciences, Université Abou Baker Belkaid, B.P. 119, 13000 Tlemcen, Algeria.
authors.forename: A
authors.initials: A
authors.lastname: Kermad
authors.affiliation: ‡Unité de Recherche Matériaux et Energies Renouvelables (URMER), Département de Physique, Faculté des Sciences, Université Abou Baker Belkaid, B.P. 119, 13000 Tlemcen, Algeria.
authors.forename: N
authors.initials: N
authors.lastname: Ghellai
authors.forename: N
authors.initials: N
authors.lastname: Gabouze
mesh_terms: D000110:Acetylcholinesterase / Q000737:chemistry* / Q000378:metabolism*; D015415:Biomarkers / Q000737:chemistry / Q000378:metabolism; D003124:Colorimetry; D004789:Enzyme Activation; D004800:Enzymes, Immobilized / Q000737:chemistry* / Q000378:metabolism*; D007700:Kinetics; D008958:Models, Molecular; D015394:Molecular Structure; D009943:Organophosphorus Compounds / Q000032:analysis; D010573:Pesticide Residues / Q000032:analysis; D012825:Silicon / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D013499:Surface Properties
chemical_list: D015415:Biomarkers; D004800:Enzymes, Immobilized; D009943:Organophosphorus Compounds; D010573:Pesticide Residues; D000110:Acetylcholinesterase; D012825:Silicon