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Molecularly imprinted polymers (MIPs) are where the complexity of receptor proteins meets the tunability of synthetic research. Receptor proteins, such as enzymes or antibodies, have functional cavities that act as docking platforms by recognizing and binding to complementary ligands. Once bound, a receptor–ligand complex may generate any multitude of cellular responses, including the regulation, uptake, and/or release of certain hormones, neurotransmitters, inorganic minerals, antigens, enzymes, and other molecules within an organism. Just like receptor proteins, MIPs are polymers with carefully selected functional groups that are spacially arranged to recognize target molecules. MIPs are generated by templating a functionalized polymer with a molecule, leaving a cavity that is complementary to the molecule upon removal. That cavity then has an affinity for the molecule that was templeted for later rebinding. The aim of MIP research is to recognize a desired target molecule with the precision of receptor proteins, and to maintain specificity and sensitivity towards the target molecule while tailoring functional properties for advanced applications. Resarchers are far from perfecting the delicate intricacy of mimicking such elegant biological processes, and improvements in all areas of MIP synthesis remain a vibrant and active topic. Various methods explored to synthesize MIPs with impressive recognition capabilities towards target molecules and the recent applications of MIPs are found herein. This review aims to dissect the synthetic steps required to generate MIPs, with emphasis on the more recent routes utilized and overall application advances. 

Nanocellulose has attracted widespread interest for applications in materials science and biomedical engineering due to its natural abundance, desirable physicochemical properties, and high intrinsic mineralizability (i.e., complete biodegradability). A common strategy to increase dispersibility in polymer matrices is to modify the hydroxyl groups on nanocellulose through covalent functionalization, but such modification strategies may affect the desirable biodegradation properties exhibited by pristine nanocellulose. In this study, cellulose nanofibrils (CNFs) functionalized with a range of esters, carboxylic acids, or ethers exhibited decreased rates and extents of mineralization by anaerobic and aerobic microbial communities compared to unmodified CNFs, with etherified CNFs exhibiting the highest level of recalcitrance. The decreased biodegradability of functionalized CNFs depended primarily on the degree of substitution at the surface of the material rather than within the bulk. This dependence on surface chemistry was attributed not only to the large surface area-to-volume ratio of nanocellulose but also to the prerequisite surface interaction by microorganisms necessary to achieve biodegradation. Results from this study highlight the need to quantify the type and coverage of surface substituents in order to anticipate their effects on the environmental persistence of functionalized nanocellulose.