Microparticles and Microcapsules from the Solvent Extraction of Deep Eutectic Solvent-Based Emulsion

Abstract

The microparticles of poly­(lactic-co-glycolic acid) (PLGA) and poly­(methyl methacrylate) (PMMA) and microcapsules of ibuprofen-PLGA, ibuprofen-polylactic acid, and ibuprofen-PMMA were successfully prepared using the solvent extraction of oil-in-deep eutectic solvent (O/DES) emulsions with dichloromethane or ethyl acetate as the solvent of the oil phase, [ChCl] [dl-malic acid] or [ChCl] [malonic acid] as the DES, and water, 1 wt % poly­(vinyl alcohol) solution in water, or ethanol as the antisolvent. The morphologies of the product microparticles and microcapsules were characterized by scanning electron microscopy and found to be dependent on the solvent of the oil phase in the O/DES emulsions rather than the other surfactants, which was essentially the outcome of interplay between polymer solution phase separation and polymer chain mobility. The encapsulation efficiencies and drug loading efficiencies of the microcapsules were determined experimentally in the ranges of 14.5–16.4% and 87.1–98.9%, respectively. The in vitro test confirmed the slow release characteristics of the product microcapsules. Additionally, the information on the miscibility of various organic solvents with DES was collected and presented as fundamental information for the formation of O/DES emulsions. The stability of O/DES emulsions was also monitored by measuring the variations of viscosity and electrical conductivity with time of the emulsion, and the results showed that the stability could be as long as 72 h. Compared to the traditional methods such as solvent evaporation of O/W emulsion and solvent extraction of O/O emulsion, the application of solvent extraction of O/DES emulsion could provide a surfactant-free route and reduce the use of harmful organic solvents, respectively.

High-gravity-assisted Fabrication of Self-assembled Colloidosomes

“…The imposed shear force governs the emulsion droplet size, thereby affecting the diameter of colloidosomes. The property of emulsions obtained by various technical means plays an important role. − However, most of the currently reported methods for emulsion preparation, such as mechanical agitation, , microfluidics, − and membrane emulsification, , are still facing a big challenge in preparing colloidosomes with a small size or realizing an industrial production.…”

Polyhedral Particles with Controlled Concavity by Indentation Templating

“… 5 − 7 Common methods for large-scale microparticle synthesis include solvent extraction or evaporation and dispersion polymerization. 8 , 9 These techniques are stochiometric in nature and thus provide limited control over particle size, shape, and chemistry and tend to make spherical particles.…”

Stability of Chlorogenic Acid from Artemisiae Scopariae Herba Enhanced by Natural Deep Eutectic Solvents as Green and Biodegradable Extraction Media

“…Natural deep eutectic solvents (NADESs) have been proposed as effective media 17 and explored for extracting bioactive substances with the targets of reducing toxic waste 18 and improving the selectivity 19 and extraction efficiency. 20 , 21 Meanwhile, the composition of NADESs may appear in every single organism, coexisting with metabolically active substances in cells.…”

“…Herein, this work proposed NADESs integrated with an ultrasound technique for extracting CGA from ASH. NADESs were designed through cheap, simple, and natural compounds 18 for the efficient and biodegradable scheme. Meanwhile, ultrasonic assistance and NADES assistance were employed as a gentle pathway for obtaining CGA to ensure better stability.…”

“…Natural deep eutectic solvents (NADESs) have been proposed as effective media and explored for extracting bioactive substances with the targets of reducing toxic waste and improving the selectivity and extraction efficiency. , Meanwhile, the composition of NADESs may appear in every single organism, coexisting with metabolically active substances in cells . This stable coexistence relationship makes NADESs excellent process solvents for gentle extraction , (lower temperature and shorter time) to protect and enhance the stability of active ingredients at the same time.…”