Restricted Access Molecularly Imprinted Polymers for Biological Sample Preparation

Restricted access molecularly imprinted polymers (RAMIPs) have been efficiently used for the extraction of small organic molecules from untreated biological matrices (e.g. blood, plasma, serum, and milk). These materials have been obtained by modifying the external surface of conventional molecularly imprinted polymers (MIPs) with hydrophilic monomer grafting, crosslinked protein capsule or a combination of both. These sorbents aggregate the selectivity of MIPs with the ability to exclude macromolecules of restricted access materials (RAMs), being widely employed in solid phase extraction techniques, beyond their use in sensors. In this review, we discuss about the design and application of RAMIPs in biological sample preparation, emphasizing the future trends and remaining challenges of this technology for bioanalyses.