Liquid-liquid phase separation of immiscible polymers at double emulsion interfaces for configurable microcapsules

Revolutionizing fixed-dose combinations with long-acting microsphere

Combination therapy, involving the concurrent use of multiple medications, has become crucial for managing complex diseases with diverse pathological mechanisms. Fixed-Dose Combinations (FDCs) are formulated to leverage the synergistic effects of multiple drugs, thereby enhancing therapeutic outcomes. However, conventional FDCs typically maintain therapeutic effects for only up to 24 h and require frequent dosing, which often results in patient non-compliance and inconsistent treatment responses, especially in chronic diseases. This highlights the urgent need for long-acting FDCs that can provide sustained drug release over extended periods-weeks, months, or even years-thereby reducing dosing frequency and enhancing patient adherence. Microspheres, with their ability to encapsulate and release multiple medications in predefined patterns, are highly advantageous for developing long-acting FDC drugs. This review emphasizes the increasing demand for long-acting FDC drugs that ensure sustained drug release, reduce dosing frequency, and ultimately improve patient adherence. We also highlight the potential of microsphere technology, which enables precise encapsulation and sustained release of multiple medications, as a promising approach for revolutionizing long-acting FDCs with enhanced therapeutic outcomes.

Encapsulation of Hydrophobic-but-Not-Lipophilic Perfluoro Liquids Based on a Self-Assembled Double Emulsion Template via Solvent Evaporation Method

The facile encapsulation of perfluoro liquids that are hydrophobic but not lipophilic into liposomes or microcapsules presents a significant challenge in the fields of biomedicine, dynamic optics, functional chemical applications, etc. This is due to their chemical inertness and physical immiscibility, particularly those with low boiling points. In this study, a novel strategy based on a double emulsion template via solvent evaporation is proposed after investigating the mechanism of three-phase emulsion systems. The perfluoro liquid droplets can be easily emulsified into a polymer solution as the second emulsion layer, where the polymer shell is formed during solvent evaporation in the continuum medium under proper processing controls. The morphology of particles is predictable and fits well with the linear model derived from Neumann's triangle in three-phase systems. Furthermore, a comprehensive study on the encapsulation of perfluoro ketone, which is widely used as a green fire extinguisher agent, is conducted as an example. The encapsulated perfluoro ketone showed instant thermal response upon heating while maintaining a good shelf life at room temperature. The remarkable fire suppression performance exhibited great potential for practical applications. This work offers more insight into the encapsulation of "naughty" perfluorinated chemicals and provides more possibilities for extended applications.

Controllable enzymatic hydrolysis in reverse Janus emulsion microreactors

HYPOTHESIS

The key feature of living cells is multicompartmentalization for enzymatic reactions. Artificial cell-like multicompartments with micro domains are appealing to mimic the biological counterparts. In addition, establishing a sustainable, efficient, and controllable reaction system for enzymatic hydrolysis is imperative for the production of natural fatty acids from animal and plant-based fats.

EXPERIMENTS

Reverse Janus emulsion microreactors, i.e. (W1 + W2)/O, is constructed through directly using natural fats as continuous phase and aqueous two-phase solutions (ATPS) as inner phases. Enzyme is confined in the compartmented aqueous droplets dominated by the salt of Na2SO4 and polyethylene glycol (PEG). Enzyme catalyzed ester hydrolysis employed as a model reaction is performed under the conditions of agitation-free and mild temperature. Regulation of reaction kinetics is investigated by diverse droplet topology, composition of inner ATPS, and on-demand emulsification.

FINDINGS

Excellent enzymatic activity toward hydrolysis of plant and animal oils achieves 88.5 % conversion after 3 h. Compartmented micro domains contribute to condense and organize the enzymes spatially. Timely removal of the products away from reaction sites of oil/water interface "pushed" the reaction forward. Distribution and transfer of enzyme in two aqueous lobes provide extra freedom in the regulation of hydrolysis kinetics, with equilibrium conversion controlled freely from 14.5 % to 88.5 %. Reversible "open" and "shut" of hydrolysis is acheived by on-demand emulsification and spontaneous demulsification. This paper paves the way to advancing progress in compartmentalized emulsion as a sustainable and high-efficiency platform for biocatalytic applications.