title: Selective and direct immobilization of cysteinyl biomolecules by electrochemical cleavage of azo linkage.
abstract: Controlled orientation and reserved activity of biomolecules, when site-selectively immobilized in a highly integrated manner on a minimal time scale, are crucial in designing biosensors for the multiplex detection. Here, we describe a novel method for the orientation-controlled immobilization of biomolecules based on site-selective electrochemical activation of p-hydroxyazobenzene self-assembled monolayer (SAM) followed by one-step coupling of cysteinyl biomolecules. The p-aminophenol, a product of reductive cleavage of p-hydroxyazobenzene, was subsequently oxidized to yield p-quinoneimine which then conjugated with cysteinyl biomolecules through 1,4-Michael addition, thus obviating additional linker agents and the related time consumption. Using this method, we selectively activated the electrode surface and immobilized laminin peptide IKVAV, a neurite promoting motif. When we cultured hippocampal neurons on the electrode, the extended neurites were found only within the electrochemically activated area. Hence, the proposed method represents a new promising platform for the patterning of functional peptides, active proteins, and live cells.
authors.affiliation: Department of Chemistry, Seoul National University, Seoul 151-747, Korea.
authors.forename: Hyun Joo
authors.initials: HJ
authors.lastname: Jung
authors.forename: Inseong
authors.initials: I
authors.lastname: Hwang
authors.forename: Beom Jin
authors.initials: BJ
authors.lastname: Kim
authors.forename: Hyegeun
authors.initials: H
authors.lastname: Min
authors.forename: Hyunung
authors.initials: H
authors.lastname: Yu
authors.forename: Tae Geol
authors.initials: TG
authors.lastname: Lee
authors.forename: Taek Dong
authors.initials: TD
authors.lastname: Chung
mesh_terms: D001391:Azo Compounds / Q000737:chemistry*; D015374:Biosensing Techniques; D002478:Cells, Cultured; D003545:Cysteine / Q000737:chemistry*; D004563:Electrochemistry; D006624:Hippocampus / Q000166:cytology; D009474:Neurons / Q000166:cytology; D010084:Oxidation-Reduction; D010455:Peptides / Q000737:chemistry; D018629:Spectrometry, Mass, Secondary Ion; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D001391:Azo Compounds; D010455:Peptides; D003545:Cysteine