Template Removal Strategies in Electropolymerized Molecularly Imprinted Polymers: Mechanisms, Challenges, and Perspectives.

Template removal represents a critical yet often underexplored step in the fabrication of electropolymerized molecularly imprinted polymers (e-MIPs), directly influencing cavity integrity, selectivity, and sensor performance. In this review, we provide a comprehensive analysis of the most commonly employed template removal strategies, including immersion-based methods and electrochemical cleaning, with a particular focus on systems based on polypyrrole (PPy) and poly(o-phenylenediamine) (PoPD). We examine how template removal conditions, such as solvent composition, pH, and applied potential, affect polymer structure, doping state, swelling behavior, and electrochemical properties. Special attention is given to mechanistic aspects such as protonation/deprotonation, overoxidation, and polymer-template interactions, which govern both remotion efficiency and potential degradation pathways. By comparing PPy and PoPD systems, we highlight how intrinsic polymer properties dictate the suitability of specific removal strategies. Additionally, we discuss emerging approaches, including multi-step template removal protocols and the incorporation of conductive nanomaterials to mitigate performance loss. This work aims to provide a mechanistic perspective on how template removal conditions affect polymer structure, electrochemical properties, and the overall performance of e-MIP-based sensors.