Study on electrode process of myoglobin at a polymerized Toluidine Blue film electrode

<正> This paper reports the use of an electrochemically polymerized Toluidine Blue （TB） filmelectrode.The film on platinum electrode surface was analyzed with ESCA.The heterogeneouselectron transfer processes of myoglobin at the polymerized TB film electrode have been investigatedusing in situ UV-visible spectroelectrochemistry.The formal potential（E°′）and electron transfernumber（n）of myoglobin were calculated as E°′=0.045 V（vs.NHE）and n=0.99.The exhaustivereduction and oxidation electrolyses are achieved in 130 s and 110 s respectively,during a potential stepbetween-0.4 V and+0.4 V.A formal heterogeneous electron transfer rate constant（ksh）of 1.09×10-4 cm/s and a transfer coefficient（α）of 0.47 were obtained by cyclic voltabsorptometry,whichindicated that myoglobin underwent a quasi-reversible electrode process at the polymerized TB filmelectrode.