We examined the direct electron transfer of horseradish peroxidase (HRP) at HRP/carbon paste (CP)-modified electrodes under irreversible electrochemical conditions. The amount of electroactive HRP (Γ) was estimated as 2.0 × 10⁻⁹ to 3.9 × 10⁻⁹ mol, indicating that the effectiveness factor, defined as the ratio of the amount of electroactive HRP to the amount of HRP incorporated into CP, was 0.14–0.24. In the presence of potassium ferricyanide(III) (K₃Fe(CN)₆) and potassium hexacyanoferrate(II) (K₄Fe(CN)₆) as mediators, the electroactive surface area of only HRP on the HRP/CP-modified electrode was 0.0164 cm². The theoretically calculated coverage area of electroactive HRP on the HRP/CP-modified electrode was much greater than the electroactive surface area of the CP electrode. In addition, the rate constant (k°) of the electrochemical reaction of HRP at the HRP/CP-modified electrode was 0.006 s⁻¹ for the oxidation process.

我们在不可逆的电化学条件下检查了辣根过氧化物酶（HRP）在HRP /碳糊（CP）修饰电极上的直接电子转移。电活性HRP（Γ）的量估计为2.0×10 ^-9至3.9×10 ^-9  mol，表明有效性因子定义为电活性HRP量与CP中所含HRP量之比。 0.14-0.24。在存在铁氰化钾（III）（K ₃ Fe（CN）₆）和六氰基铁酸钾（II）（K ₄ Fe（CN）₆）作为介体的情况下，仅在HRP / CP修饰的HRP上的电活性表面积电极为0.0164 cm ²。从理论上计算，HRP / CP修饰电极上电活性HRP的覆盖面积远大于CP电极的电活性表面积。另外，对于HRP / CP修饰电极，HRP的电化学反应的速率常数（k °）为0.006s ^-1。