Selective and Direct Immobilization of Cysteinyl Biomolecules by Electrochemical Cleavage of Azo Linkage

• Published in: Langmuir Vol. 26; no. 19; pp. 15087 - 15091
• Main Authors: Jung, Hyun Joo, Hwang, Inseong, Kim, Beom Jin, Min, Hyegeun, Yu, Hyunung, Lee, Tae Geol, Chung, Taek Dong
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 05.10.2010
• Subjects: Azo Compounds - chemistry; Biosensing Techniques; Cells, Cultured; Chemistry; Cysteine - chemistry; Electrochemistry; Exact sciences and technology; General and physical chemistry; Hippocampus - cytology; Neurons - cytology; Oxidation-Reduction; Peptides - chemistry; Spectrometry, Mass, Secondary Ion; Spectroscopy, Fourier Transform Infrared; Michael addition; Electrodes; Self assembly; Monolayer; Patterning; Peptides; Biosensor; Electrochemistry; Immobilization; Activation; Orientation; Protein
• ISSN: 0743-7463; 1520-5827
• DOI: 10.1021/la102489k

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.