Unifying Common Protein-Film Square-Wave Voltammetric Mechanisms within a Single Theoretical Framework: Simulation Protocol in Mathcad

Protein-film square-wave voltammetry (SWV) provides a powerful approach for probing electron-transfer reactions and coupled chemical processes of surface-confined redox systems. However, individual reaction mechanisms are commonly treated using separate theoretical models, making systematic comparison between related pathways difficult. In this work, we present a unified theoretical framework that integrates several common mechanisms encountered in protein-film voltammetry within a single computational model. By appropriate adjustment of kinetic and thermodynamic parameters, the model reproduces characteristic voltammetric behavior associated with simple electron transfer, coupled preceding irreversible and intermediate reversible chemical reactions, sequential electron-transfer steps, and catalytic transformations associated to the second electron transfer step. Particular attention is given to the relationships between kinetic parameters and experimentally accessible SWV features, including peak potentials, peak currents, forward and backward components, and peak morphology. The framework therefore provides a systematic basis for recognizing mechanistic transitions and distinguishing between related reaction pathways. Beyond its theoretical significance, the proposed approach offers a practical tool for mechanistic interpretation and kinetic analysis of complex surface-confined redox processes by square-wave voltammetry. The Mathcad simulation protocol provided in this work enables straightforward generation and systematic exploration of different mechanistic scenarios by varying the relevant kinetic and thermodynamic parameters. It therefore provides a practical computational tool for testing reaction pathways, identifying characteristic voltammetric signatures, and supporting mechanistic discrimination and kinetic analysis. The proposed framework connects apparently different protein-film voltammetric mechanisms within a common theoretical and computational basis.