Characteristic and Applications for Functionalization of Solid Interface via Click Chemistry Stratages
|School||East China Normal University|
|Keywords||Surface chemistry Electrochemistry Surface functionizition Click chemistry Michael reaction|
Chapter one:PerfaceA number of interfacial chemoselective strategies including Oxime reaction, Diels-Alder conjugation, Click chemistry, Staudinger ligation, Thiol-ene reaction, Michael addition, Supermolecular chemistry and Photo-grafting have been developed to immobilize and present a variety of ligands on the surface. Basic concept, characteristic, methods for characterization and applications of surface functionalization are introduced.Chapter two:High-Quality Covalently Grafting Hemoglobin on Gold Electrodes: Characterization, Redox Thermodynamics and Bio-electrocatalysisHerein, we report a versatile surface chemistry methodology to covalently immobilize ligands and proteins to self-assembled monolayers (SAMs) on gold electrode. The strategy is based on two steps:1) the coupling of soluble azido-PEG-amimo ligand with an alkynyl-terminated monolayer via click reaction and 2) covalent immobilization hemoglobin (Hb) to the amine-terminated ligand via carbodiimide reaction. Surface-enhanced Raman scattering spectroscopy (SERS), atomic force microscopy (AFM), reflection absorption infrared spectroscopy (RAIR) and cyclic voltammetry are used to characterize the model interfacial reactions. We also demonstrate the excellent biocompatibility of the interface for Hb immobilization and reliable application of the proposed method for H2O2 biosensing. Moreover, the redox thermodynamics of the Fe3+/Fe2+ couple in Hb is also investigated.Chapter three:Electrochemically Triggered Michael Addition on the Self-Assembly of 4-Thiouracil:Generation of Catechol Terminated Monolayers and Complex with Ni (Ⅱ) and Cu (Ⅱ)In this paper, catechol,1,4-dihydroxybenzene and dopamine are investigated as precursor of electrophiles for Michael addition reaction with the self-assembled monolayer (SAM) of 4-thiouracil (4-TU) via electrochemical triggering. All compounds can undergo Michael addition reaction with 4-TU, however, only catechol can conduct with high efficiency. The catechol-terminated SAMs via electrochemically triggered Michael addition reaction exhibit reversible redox response. In addition, we find that catechol-terminated SAMs can complex with Ni2+ and Cu2+ with different electrochemical behaviors. Moreover, the mechanism of . complexation of Ni2 +and Cu2+ with catechol-terminated SAMs is also demonstrated with electrochemical and spectrometric methods. Based on the different electrochemical behaviors of Cu2+ and Ni2+ complex, the catechol-terminated SAMs provide a potential platform for metal ions recognition.Chapter four:Determination of Physiological Thiols by Electrochemical Detection with Catechol-modified Au electrode and Its Application in Inhibitor Screening for AcetylcholinesteraseThe nucleophilic addition of the aminothiols cysteine (CYS) and glutathione (GSH) to the electrogenerated o-quinone of Catechol-terminated.SAMs is reported. The modified electrode displayed a good current response to physiological thiols. The linear ranges are 1.0×10-9 to 2.2×10-7M for CYS and 1.0×10-9 to 1.3×10-7M for GSH. Moreover, this method is also useful for activity study and screening inhibitors of AChE.