Strategies to remove templates from molecularly imprinted polymer (MIP) for biosensors

Molecularly imprinted polymers (MIP) have been of significant interest, especially for usage as recognition elements in biosensors. The sensitivity of a biosensor is largely governed by the interactions between the analyte and the recognition element. This represents a challenge for molecularly imprinted polymers as the interaction with the analyte relies on the successful creation of a template imprint. A crucial part of the process is the removal strategy of the template from the surrounding polymeric network. Since the inception of the field, there have been many strategies for this removal process, and these are the topic of this review. The focus is on template removal strategies from MIPs utilized for diagnostic biosensors. The literature survey of various strategies can be summarized into chemical-based and electrochemical-based template extraction. Generally, for chemical extraction solvents and acids are employed, whereas for electrochemical extraction, cyclic voltammetry is commonly used. These approaches are summarized and evaluated in the current review to provide guidance to researchers working in the areas of analytical chemistry, diagnostics, and materials science to better design MIP-based sensors.