The electrochem. behavior of myoglobin at a Brilliant Cresyl Blue (BCB) modified platinum gauze electrode and spiral Pt wire in the BCB solution in optically transparent thin layer cell has been investigated by using cyclic potential-absorbance method and double potential step chronoabsorptiometry. The results reveal a reversible electron transfer reaction of myoglobin. Exhaustive reductive and oxidative electrolyses are achieved at the modified platinum surface in 20 and 100 s resp. The formal heterogenous electron transfer rate constant is estimated (ks = 1.87 ?10-2 cm/s). The stability of electrode reaction is improved, and no denaturation occurred. The formal electrode potential and electron transfer no. of this reaction are determine by using a spectroelectrochem. method, and the results are in agreement with literature. Myoglobin does not absorb at BCB modified platinum gauze electrode, which has been confirmed by ESCA. The mechanism for the heterogeneous electron transfer of myoglobin at BCB modified electrodes is discussed.

Key words: OXIDATION REDUCTION REACTION, ELECTRODE, CHEMICAL MODIFIED ELECTRODE, REVERSIBLE PROCESS, CRESOL P, MYOGLOBIN, ELECTRON TRANSFER REACTION