Molecular Engineering of Metal-Organic Cycles/Cages for Drug Delivery

The assembly of nanoscale materials with well-defined size and shape is an intriguing approach to aid in drug design and delivery. Of the various nano-structures that have been synthesised, metal-organic cycles and cages (MOCs), featuring great structural versatility, have emerged as promising components in cancer chemotherapeutics. We review the recent progress of exploiting self-assembled MOCs as anticancer drugs as well as drug carriers. Particularly molecular engineering designs allow MOCs to carry drugs with specificity, and interface with biological systems whilst possessing the desired stability, cytotoxicity, and compatibility. A special focus is given to the functionalization method of integrating MOCs with polymers, leading to the synthesis of colloidal nanoparticles-micelles and vesicles-that possess combined properties and extended system tunability.