A new design for an artificial cell: polymer microcapsules with addressable inner compartments that can harbor biomolecules, colloids or microbial species.

Eukaryotic cells have an architecture consisting of multiple inner compartments (organelles) such as the nucleus, mitochondria, and lysosomes. Each organelle is surrounded by a distinct membrane and has unique internal contents; consequently, each organelle has a distinct function within the cell. In this study, we create biopolymer microcapsules having a compartmentalized architecture as in eukaryotic cells.

Photocatalytic Oxidation of Sulfur Mustard and Its Simulant on BODIPY-Incorporated Polymer Coatings and Fabrics.

Sulfur mustard is one of the most toxic chemical warfare agents worldwide. We report the use of 4,4-difluoro-4-bora-3a,4a-diaza- s-indacene (BODIPY) photosensitizers as a fast and effective sulfur mustard decontaminant and their incorporation into various polymer coatings and fabrics, including army combat uniform. These BODIPY-embedded materials are capable of generating singlet oxygen under visible light irradiation and effectively detoxifying sulfur mustard by converting it into nontoxic sulfoxides as the major products.

MOFwich: Sandwiched Metal-Organic Framework-Containing Mixed Matrix Composites for Chemical Warfare Agent Removal.

This work describes a new strategy for fabricating mixed matrix composites containing layered metal-organic framework (MOF)/polymer films as functional barriers for chemical warfare agent protection. Through the use of mechanically robust polymers as the top and bottom encasing layers, a high-MOF-loading, high-performance-core layer can be sandwiched within. We term this multifunctional composite "MOFwich".

Tuning the Morphology and Activity of Electrospun Polystyrene/UiO-66-NH Metal-Organic Framework Composites to Enhance Chemical Warfare Agent Removal.

This work investigates the processing-structure-activity relationships that ultimately facilitate the enhanced performance of UiO-66-NH metal-organic frameworks (MOFs) in electrospun polystyrene (PS) fibers for chemical warfare agent detoxification. Key electrospinning processing parameters including solvent type (dimethylformamide [DMF]) vs DMF/tetrahydrofuran [THF]), PS weight fraction in solution, and MOF weight fraction relative to PS were varied to optimize MOF incorporation into the fibers and ultimately improve composite performance. It was found that composites spun from pure DMF generally resulted in MOF crystal deposition on the surface of the fibers, while composites spun from DMF/THF typically led to MOF crystal deposition within the fibers.

Imaging and Analysis of Encapsulated Objects through Self-Assembled Electron and Optically Transparent Graphene Oxide Membranes.

We demonstrate a technique for facile encapsulation and adhesion of micro- and nano objects on arbitrary substrates, stencils, and micro structured surfaces by ultrathin graphene oxide membranes via a simple drop casting of graphene oxide solution. A self-assembled encapsulating membrane forms during the drying process at the liquid-air and liquid-solid interfaces and consists of a water-permeable quasi-2D network of overlapping graphene oxide flakes. Upon drying and interlocking between the flakes, the encapsulating coating around the object becomes mechanically robust, chemically protective, and yet highly transparent to electrons and photons in a wide energy range, enabling microscopic and spectroscopic access to encapsulated objects.

MOFabric: Electrospun Nanofiber Mats from PVDF/UiO-66-NH for Chemical Protection and Decontamination.

Textiles capable of capture and detoxification of toxic chemicals, such as chemical-warfare agents (CWAs), are of high interest. Some metal-organic frameworks (MOFs) exhibit superior reactivity toward CWAs. However, it remains a challenge to integrate powder MOFs into engineered materials like textiles, while retaining functionalities like crystallinity, adsorptivity, and reactivity.

Light-Directed Self-Assembly of Robust Alginate Gels at Precise Locations in Microfluidic Channels.

Recently there has been much interest in using light to activate self-assembly of molecules in a fluid, leading to gelation. The advantage of light over other stimuli lies in its spatial selectivity, i.e.

Catalytic Propulsion and Magnetic Steering of Soft, Patchy Microcapsules: Ability to Pick-Up and Drop-Off Microscale Cargo.

We describe the creation of polymeric microcapsules that can exhibit autonomous motion along defined trajectories. The capsules are made by cross-linking aqueous microdroplets of the biopolymer chitosan using glutaraldehyde. A coflow microfluidic tubing device is used to generate chitosan droplets containing nanoparticles (NPs) with an iron (Fe) core and a platinum (Pt) shell.

Microfluidic generation of uniform water droplets using gas as the continuous phase.

Microfluidic schemes for forming uniform aqueous microdroplets usually rely on contacting the aqueous liquid (dispersed phase) with an immiscible oil (continuous phase). Here, we demonstrate that the oil can be substituted with gas (nitrogen or air) while still retaining the ability to generate discrete and uniform aqueous droplets. Our device is a capillary co-flow system, with the inner flow of water getting periodically dispersed into droplets by the external flow of gas.

Microfluidic assembly of Janus-like dimer capsules.

We describe the microfluidic assembly of soft dimer capsules by the fusion of individual capsules with distinct properties. Microscale aqueous droplets bearing the biopolymer chitosan are generated in situ within a chip and, as they travel downsteam, pairs of droplets are made to undergo controlled cross-linking and coalescence (due to a channel expansion) to form stable dimers. These dimers are very much like Janus particles: the size, shape, and functionality of each individual lobe within the dimer can be precisely controlled.