Injectable liposome-containing click hydrogel microparticles for release of macromolecular cargos

Area of Science:

• Biomaterials Science
• Drug Delivery Systems
• Microfluidics

Background:

• Hydrogel microparticles (microgels) offer advantages for biological applications due to their injectability and modularity.
• Existing methods for microgel production require expansion to meet diverse therapeutic needs.

Purpose of the Study:

• To establish a microfluidic method for producing poly(ethylene) glycol (PEG)-based microgels and liposomes-containing microgels (lipo-microgels).
• To characterize the physicochemical properties and cargo delivery capabilities of the developed microgels.

Main Methods:

• Droplet-based microfluidics was employed to synthesize PEG-based microgels and lipo-microgels via Michael-type addition reactions.
• Microgel size, morphology, liposome presence, mechanical properties (AFM), and cargo release kinetics were analyzed.

Main Results:

• Uniform spherical microgels (74 ± 16 μm) and lipo-microgels (82 ± 25 μm) were successfully produced, confirmed by microscopy.
• Rheological analysis supported the injectability of the microgels.
• Sustained release of model cargo (FITC-Dextran 5 kDa) and protein (equine myoglobin) was observed for up to 3 weeks, with preserved protein structure.

Conclusions:

• The microfluidic method provides a versatile platform for creating injectable PEG-based microgels and lipo-microgels.
• These microgels demonstrate potential for protecting and controlling the release of therapeutic cargos, including proteins.