Versatile preparation of spherically and mechanically controllable liquid-core-shell alginate-based bead through...

Area of Science:

• Materials Science
• Polymer Chemistry
• Chemical Engineering

Background:

• Alginate-based beads with liquid-core-shell structures are attractive for industrial delivery applications.
• Developing facile and scalable methods for producing such beads is crucial.

Purpose of the Study:

• To propose a facile method for fabricating alginate beads with a liquid-core-shell structure via interfacial gelation.
• To investigate the influence of core and shell properties on bead formation and mechanical characteristics.

Main Methods:

• Utilizing a reaction-diffusion mechanism for bead formation.
• Dissolving natural polymers in a calcium ion core solution and dripping into an alginate shell bath.
• Tuning viscosity, surface tension, calcium ion concentration, and reaction time.

Main Results:

• A universal viscosity-boundary relationship was established, independent of core polymer type or charge.
• Chitosan in the core significantly impacted mechanical properties due to polyelectrolyte interactions with alginate.
• Surfactant addition to the shell bath increased the spherical zone of bead formation.
• Increased calcium ion concentration and reaction time enhanced shell membrane compactness and mechanical properties.

Conclusions:

• The proposed interfacial gelation method offers a facile route to alginate beads with liquid-core-shell structures.
• Controlling interfacial properties and polymer interactions is key to tailoring bead characteristics for delivery applications.
• This approach provides a versatile platform for developing advanced delivery matrices.