Biomimetic Antithrombogenic Electrochemical Superoxide Anion Radical Sensor

An antithrombogenic electrochemical superoxide anion radical (O2(center dot-)) sensor was developed based on the concept of biomimetics. The sensor was fabricated by modification of a carbon microelectrode surface with polymerized iron 5,10,15,20-tetra(3-thienyl) porphyrin (FePor), followed by coating with a polyethylenedioxythiophene (PEDOT)/heparin or PEDOT/carboxymethyl dextran sulfate (CMDS) layer. The antithrombogenic superoxide anion radical sensors exhibited an amperometric oxidation current for O2(center dot-), even after immersion of the sensor in bovine blood for 2 weeks, while the sensor without the PEDOT/heparin (or CMDS) layer had no response current after immersion in bovine blood for 1 h. The response current to 1 mu M O2(center dot-) was almost constant at the PEDOT/CMDS-FePor-modified electrode after immersion in bovine blood for 1-14 days, and good linearity was observed in the concentration range between 0.52 and 1.80 mu M, which is suitable sensitivity for the quantitative determination of O center dot- in human blood. The PEDOT/CMDS-FePor-modified electrode contains no bio-derived compounds; therefore, its use as an antithrombogenic superoxide anion radical sensor should be safe, even when used in vivo. (C) 2014 The Electrochemical Society. All rights reserved.