Microfluidic Droplet-Facilitated Hierarchical Assembly for Dual Cargo Loading and Synergistic Delivery

Bottom-up hierarchical assembly has emerged as an elaborate and energy-efficient strategy for the fabrication of smart materials. Herein, we present a hierarchical assembly process, whereby linear amphiphilic block copolymers are self-assembled into micelles, which in turn are accommodated at the interface of microfluidic droplets via cucurbit[8]uril-mediated host-guest chemistry to form supramolecular microcapsules. The monodisperse microcapsules can be used for simultaneous carriage of both organic (Nile Red) and aqueous-soluble (fluorescein isothiocyanate-dextran) cargo. Furthermore, the well-defined compartmentalized structure benefits from the dynamic nature of the supramolecular interaction and offers synergistic delivery of cargos with triggered release or through photocontrolled porosity. This demonstration of premeditated hierarchical assembly, where interactions from the molecular to microscale are designed, illustrates the power of this route toward accessing the next generation of functional materials and encapsulation strategies.

Janus Suprabead Displays Derived from the Modified Photonic Crystals toward Temperature Magnetism and Optics Multiple Responses

The design and development of Janus suprabeads (JSs) with multiple responses are highly desirable in the fabrication of functional nanomaterials. In this work, we report a triphase microfluidic strategy for the construction of JSs with temperature-magnetism-optics triple responses. Initially, macromonomer poly(methacrylic acid) (PMAA) obtained via catalytic chain transfer polymerization (CCTP) was grafted onto the polystyrene (PS) colloidal photonic crystals (CPCs) surface. Because abundant carboxylic acid groups in PMAA could coordinate cadmium ions for in situ production of fluorescent CdS quantum dots (QDs) after introducing sulfur ions, the as-prepared JSs were endowed with favorable optical properties. Meanwhile, the as-prepared Cd(2+)/PS CPCs were employed as a template to build JSs with temperature-magnetism sensitivity via the introduction of magnetic Fe3O4 and hydrogels. Finally, the fluorescence pattern was easily performed by using chalcogenides as "ink" to write on the pad, in which in situ reaction mechanism was involved in the response. The multiple responsive JSs show promising applications in sensor, display, and anticounterfeit fields.