Electrochemical Detection of Peroxynitrite Using a Biosensor Based on a Conducting Polymer−Manganese Ion Complex

摘要

A peroxynitrite (ONOO-) biosensor has been developednthrough the preparation of a new manganese-[poly-n2,5-di-(2-thienyl)-1H-pyrrole)-1-(p-benzoicacid)](Mn-pDPB)ncomplex. DPB monomer was first synthesized andnpolymerized for the purpose of providing a polymernbackbone for complex formation with Mn2+ ion. ThenMn-pDPB complex was characterized via MagnetomotivenForce (MMF) simulation, X-ray photoelectronnspectroscopy (XPS), and cyclic voltammetry. The complexnselectively enhanced the reduction process ofnONOO- which was used as the analytical signal fornchronoamperometric detection. A polyethyleneimminen(PEI) layer was coated on the complex surface tonincrease selectivity and stability. The chronoamperometricncalibration plot showed the hydrodynamic rangenof 2.0 × 10-8-5.0 × 10-7 M. The detection limit wasndetermined to be 1.9 ((0.2) × 10-9 M based on S/Nn) 3. The microbiosensor, fabricated on a 100 μmndiameter Pt tip, was applied in a real rat plasmansample for the detection of spiked concentrations ofnONOO-. The reliability and long-term stability of thenmicrobiosensor was also examined with YPEN-1 cellsnin vitro, and the results shown were promising.