Rigorous recognition mode analysis of molecularly imprinted polymers—Rational design, challenges, and opportunities

Supramolecular chemistry now presents an elaborate "enabling tool" that offers exciting opportunities for novel functional material design. One of the areas to benefit from recent advances in supramolecular chemistry is the field of molecularly imprinted polymers (MIPs), also known as "synthetic antibodies". It uses the memory of template molecules to form tailor-made binding sites in the polymer matrix. This review provides insights from rigorous recognition mode analysis perspectives and highlights evolving approaches in MIPs. First, the principles and recognition mode of molecular imprinting technology are carefully reviewed. The similarities and major differences between MIPs and enzymes are discussed. The internal 3D structure model of MIP is depicted, the origin and consequences of binding site heterogeneity are highlighted, and methods for the optimization of the recognition degree and imprinting efficiency are summarized. The criteria for evaluating imprinting efficacy and the role of chiral recognition in molecular imprinting are discussed. Subsequently, important approaches for the design and synthesis of MIPs a reviewed. Relevant approaches include dye displacement strategy for MIP sensors, multi-functional group recognition, monomolecular imprinting using dendrimers, solvent programmable polymer (SPP) based on restricted rotation, template activated molecular imprinting strategy, molecular imprinting with click chemistry, and evolution of molecular imprinting with computational strategies. Finally, the exciting progress of MIPs for recognition of biomacromolecules such as proteins, bacteria and viruses are discussed. The goal of this review is thus to inspire new applications of MIP materials and to provide a guide for how these applications might become a reality.