Chang-Hyung Choi

The rapid expansion of personalized precision medicine and the increasing prevalence of chronic diseases have rekindled crucial needs for individualized therapeutic drug delivery systems. Conventional oral formulations are largely based on standardized designs for mass production and therefore lack the flexibility required for patient‐specific therapeutic strategies, including combination dosing and controlled release. We report a rapid microfluidic fabrication method for millimeter‐scale hydrogel capsules (macrocapsules) as a versatile platform suitable for oral delivery of therapeutics. Our technique enables reliable production of uniform macrocapsules containing multiple aqueous cores physically isolated by oil layers within an alginate hydrogel shell. Independent control of flow rates and alginate formulation allows systematic tuning of capsule size, multicore organization, and cargo loading. These macrocapsules maintain structural integrity under physiologically relevant mechanical and chemical stress conditions mimicking gastric environments, effectively protecting sensitive cargos throughout the typical gastric residence time. Simple tuning of the alginate concentration can further modulate the release onset and profile in intestinal conditions in a precisely controlled manner. The platform can be easily extended to produce multicompartmental macrocapsules that accommodate multiple cargos with independent and programmable release without cross‐interference. Combined, these results represent a significant step toward versatile and programmable oral therapeutic delivery systems.

Nanoemulsions are widely recognized as versatile delivery platforms capable of stably loading lipophilic active ingredients. Although low-energy phase inversion methods enable nanoemulsion formation under ambient and low-shear conditions, their scalability and applicability in practical formulation environments remain insufficiently validated. Here, we develop oil-in-water (O/W) nanoemulsions via a low-energy phase inversion process and systematically investigate their composition-dependent formation, scalability, and formulation stability. By precisely tuning the composition of a mixed nonionic surfactant system, monodisperse nanoemulsions with an average droplet size of ~110 nm and a polydispersity index (PDI ≤ 0.20) are reproducibly obtained under ambient, low-shear conditions. The optimized nanoemulsions maintain their nanoscale dispersion characteristics over 30 days of storage and exhibit consistent droplet size and distribution upon scale-up to 1 L. Furthermore, the nanoemulsions retain structural stability when incorporated into polymer-based formulations under various temperature conditions and repeated thermal cycling. These results demonstrate that low-energy phase inversion enables a scalable and formulation-compatible nanoemulsion platform, providing practical guidelines for industrial formulation and manufacturing of delivery systems for lipophilic active ingredients.

Metal–organic frameworks (MOFs) have gained a lot of attention as an emerging photocatalyst because of their distinct features. In this study, an innovative hybrid photocatalyst was created by combining Bi ₂ S ₃ and MIL‐100(Fe) to form Bi ₂ S ₃ @MIL‐100 nanocomposite using a simple hydrothermal approach. A variety of characterization methods like FTIR, XRD, scanning electron microscope (SEM), and EDX spectroscopy were employed to describe the materials that were synthesized. The degradation efficiency of Bi ₂ S ₃ , MIL‐100, and Bi ₂ S ₃ @MIL‐100 nanocomposites was determined using UV–Vis spectroscopy under various circumstances such as pH and contact time for the removal of bromophenol blue (BPB). The nanocomposite showed 97% degradation efficiency for the time of 80 min to remove BPB. To better understand dye photodegradation, the Langmuir–Hinshelwood model was applied to experimental data. Experiments using trapping showed that the superoxide radicals (O₂• ⁻ ) are the main active species in charge of the photodegradation of bromophenol blue over Bi ₂ S ₃ @MIL‐100, while hydroxyl radicals (•OH) and holes (h ⁺ ) play secondary roles. This implies that the process of degradation is mainly governed by reactive oxygen species (ROS) rather than direct oxidation by photo‐generated holes. The Bi ₂ S ₃ @MIL‐100 nanocomposite exhibited excellent stability and reusability, maintaining high photodegradation efficiency over four consecutive cycles.

Oral delivery of hydrophobic compounds remains challenging due to their poor aqueous solubility and the potential toxicity associated with conventional surfactant-based emulsions. To address these issues, we present a surfactant-free encapsulation strategy using electrosprayed alginate hydrogel beads for the stable and controlled delivery of hydrophobic oils. Hydrophobic compounds were dispersed in high-viscosity alginate solutions without surfactants via ultrasonication, forming kinetically stable oil-in-water dispersions. These mixtures were electrosprayed into calcium chloride baths, yielding monodisperse hydrogel beads. Higher alginate concentrations improved droplet sphericity and suppressed phase separation by enhancing matrix viscosity. The resulting beads exhibited stimuli-responsive degradation and controlled release behavior in response to physiological ionic strength. Dense alginate networks delayed ion exchange and prolonged structural integrity, while elevated external ionic conditions triggered rapid disintegration and immediate payload release. This simple and scalable system offers a biocompatible platform for the oral delivery of lipophilic active compounds without the need for surfactants or complex fabrication steps.

Although oral delivery of therapeutic agents offers numerous benefits, its application is limited due to the digestive tract's harsh conditions (e.g., strong acidity and high osmolarity), which impair activity and create challenges in achieving targeted release into the intestine. Here, we present multicompartmental hydrogel microspheres equipped with a concentric oil layer to significantly enhance the oral drug delivery efficiency for treating inflammatory bowel disease (IBD). These microspheres are created through the utilization of triple-emulsion droplets, featuring intermediate oil layers that distinctively separate two prepolymer phases, allowing us to fine-tune the composition of each compartment through a tailored polymerization strategy. We demonstrate that the oil layer can protect the encapsulated material by preventing exposure to the acidic environment of the stomach during the digestive process. Unlike aqueous core capsules, the core is composed of hydrogel, which provides high stability even under high osmolarity conditions in the stomach. By fine-tuning the shell's composition, we can develop capsules that release selectively in response to the gut's pH conditions. We demonstrate the system's efficacy by preserving the anti-inflammatory activities of 5-aminosalicylic acid (5-ASA) and Lys-Pro-Val (KPV) under stomach conditions and maintaining their therapeutic effects on colonic epithelial cell migration and proliferation.