Molecularly imprinted polymers (MIPs) are novel polymeric networks that exhibit valuable pharmaceutical properties, making them a promising tool for drug delivery systems (DDSs). These unique polymers offer an appropriate approach to increasing the bioavailability of drugs and protecting target molecules under harsh conditions. The double-imprinting technique is a convenient method to achieve favorable responses for targeted delivery and can reduce the undesired effects of drugs.

Numerous studies have utilized nanotechnology to design controlled-release systems. MIPs are effective reservoirs that optimize the release and bioavailability of medications. As stimuli-responsive DDSs, MIPs are widely used to achieve the precise release of target molecules caused by endo- or exogenous stimuli. Thus, the primary focus of this chapter is on implementing novel MIP-based DDSs and their main features. Moreover, MIPs have been utilized as theranostic agents to understand better how interventions impact the site of action and monitor the drug delivery process. The theranostic MIPs provide a valuable tool for achieving precise and real-time monitoring of drug release, enabling researchers to optimize drug delivery systems and improve patient outcomes.

In this chapter, we also aim to investigate the features of MIPs that aid tissue engineering by enabling the production of scaffolds with controlled release of growth factors or other active substances, cell binding ability, and the capability to contribute to cell migration and proliferation. MIPs are introduced as suitable alternatives to neutral antibodies due to their biocompatibility, lower toxicity, and ability to imprint a wide range of templates, including ions, small molecules, peptides, viruses, bacteria, and even cells. In addition, the simplicity of production, lower immunogenicity, ability to sustain release for an extended period, endurance of harsh conditions, and lower costs make these artificial antibodies suitable for enhancing drug delivery systems. Despite the exciting and unique features of MIPs mentioned above, further research is needed to optimize previous synthesis methods and propose new ones, especially for imprinting larger molecules like peptides, to determine long-term safety and compatibility with biological systems.