Metal-Organic Framework Composites for Theragnostics and Drug Delivery Applications

Among a plethora of nano-sized therapeutics, metal-organic frameworks (MOFs) have been some of the most investigated novel materials for, predominantly, cancer drug delivery applications. Due to their large drug uptake capacities and slow-release mechanisms, MOFs are desirable drug delivery vehicles that protect and transport sensitive drug molecules to target sites. The inclusion of other guest materials into MOFs to make MOF-composite materials has added further functionality, from externally triggered drug release to improved pharmacokinetics and diagnostic aids. MOF-composites are synthetically versatile and can include examples such as magnetic nanoparticles in MOFs for MRI image contrast and polymer coatings that improve the blood-circulation time. From synthesis to applications, this review will consider the main developments in MOF-composite chemistry for biomedical applications and demonstrate the potential of these novel agents in nanomedicine. It is concluded that, although vast synthetic progress has been made in the field, it requires now to develop more biomedical expertise with a focus on rational model selection, a major comparative toxicity study, and advanced targeting techniques.