Способ ковалентной иммобилизации белка на поверхности планарного платинового электрода с использованием электропроводящих полимерных покрытий на основе 3-этинилтиофена

Аннотация

In this work we proposed an original approach for the covalent immobilization of proteins on the surface of planar platinum (Pt) electrode modified with electrodeposited polymer films, based on 3-ethynylthiophene (ETh), via “click” reaction of copper catalyzed azide-alkyne cycloaddition (CuAAC). To obtain such “clickable” functional films, three strategies have been applied: (1) the electrochemical polymerization of ETh as single monomer, (2) co-polymerization with 3,4-ethylendioxythiophene (EDOT) and (3) layer-by- layer electrodeposition EDOT-Eth composite polymer films. The modified electrodes were characterized by the cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM). The best combination of the electroconductivity and CuAAC-reactivity have demonstrated the layer-by-layer immobilized EDOT-ETh composite films. The bovine serum albumin (BSA) and antibodies have been successfully immobilized on the surface of planar platinum electrode using the developed approach. It has been applied to a label-free electrochemical immunosensor for Escherichia coli (E. coli) and Staphylococcus aureus (S.aureus) determination. The immunosensors demonstrated good analytical characteristics (LODs 4.2 CFU / ml for E. coli and 5.3 CFU / ml - for S. aureus, linear range 102-106 CFU / ml) and could be promising for environmental and food control.