Differentially Addressable Cavities within Metal–Organic Cage-Cross-Linked Polymeric Hydrogels

Here we report a new class of hydrogels formed by polymers that are cross-linked through subcomponent self-assembled metal-organic cages. Selective encapsulation of guest molecules within the cages creates two distinct internal phases within the hydrogel, which allows for contrasting release profiles of related molecules depending on their aptitude for encapsulation within the cages. The hydrogels were fabricated into microparticles via a droplet-based microfluidic approach and proved responsive to a variety of stimuli, including acid and competing amine or aldehyde subcomponents, allowing for the triggered release of cargo.