The electrochemistry of catalase (CAT) was investigated at the interface between two immiscible electrolyte solutions (ITIES) as a step towards its detection. Electrochemistry at the ITIES offers advantages such as the non-redox detection of biomolecules. The electrochemical behaviour of CAT at the ITIES, in a micro-interface array format, displayed a distinct cyclic voltammogram when the aqueous phase pH was lower than the isoelectric point (pI) of CAT. No voltammetric response was observed when the aqueous phase pH > pI of CAT, indicating that neutral or negatively charged CAT has no capability to facilitate anion transfer from the organic phase. Adsorptive stripping voltammetry (AdSV) was assessed for detection of low concentrations at the µITIES array. Application of a positive preconcentration potential for a fixed time enabled interfacial accumulation of CAT as a complex; subsequently, a voltammetric scan to lower potentials desorbed the complex, providing the electroanalytical signal. Assessment of sample matrix effects by examining the electrochemistry of CAT in artificial serum indicated that detection in pH-adjusted samples is feasible. Together, these results demonstrate that CAT is electroactive at the liquid–liquid interface and this may be useful as a strategy to detect and characterize the enzyme in a label-free manner.

在两种不混溶的电解质溶液（ITIES）之间的界面处研究了过氧化氢酶（CAT）的电化学过程，以此作为对其进行检测的一步。IES的电化学技术具有诸如生物分子的非氧化还原检测等优势。当水相pH值低于CAT的等电点（pI）时，在IES上CAT的电化学行为以微界面阵列形式显示出明显的循环伏安图。当CAT的水相pH> pI时，未观察到伏安响应，表明中性或带负电荷的CAT不具有促进阴离子从有机相转移的能力。评估了吸附溶出伏安法（AdSV）在µITIES阵列中的低浓度检测。在固定时间内施加正的预富集潜力可以使CAT作为复合物进行界面蓄积；随后，进行伏安扫描以降低电势，使复合物解吸，从而提供电分析信号。通过检查人造血清中CAT的电化学来评估样品基质的影响，表明在pH调节的样品中进行检测是可行的。总之，这些结果表明CAT在液-液界面上具有电活性，这可能有助于以无标记的方式检测和表征酶的策略。通过检查人造血清中CAT的电化学来评估样品基质的影响，表明在pH调节的样品中进行检测是可行的。总之，这些结果表明CAT在液-液界面上具有电活性，这可能有助于以无标记的方式检测和表征酶的策略。通过检查人造血清中CAT的电化学来评估样品基质的影响，表明在pH调节的样品中进行检测是可行的。总之，这些结果表明CAT在液-液界面上具有电活性，这可能有助于以无标记的方式检测和表征酶的策略。