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so-lled sho d o ncr ent 2008 Elsevier B.V. All rights reserved. nanotu eld-eff [1–3] roperti of ph rmed bled with water-soluble iron(III) meso-tetrakis (N-methylpyridi-num-4-yl)porphyrin (FeTMPyP) via electrostatic interaction. The formed SWNTs/PBA/FeTMPyP film showed excellent electrolysis toward reduction of both oxygen and nitric oxide (NO). NO is one of the most exciting sources of knowledge in biology due to its physiological and pathological roles [10]. The accurate measurement of NO is crucial for further understanding its numer-Chromatogramin Center (China). 2.2. Apparatus Cyclic voltammetric experiments were performed on a BAS electrochemical workstation (Epsilon, USA) at room temperature using a conventional three-electrode system with a modified GE as working, a platinum wire as auxiliary and a saturated calomel electrode as reference electrodes. Fourier-transform infrared spec-tra (FTIR) were obtained on a NEXUS 870 FTIR instrument (Nicolet, * Corresponding authors. Tel./fax: +86 25 83593593