Formation of polymeric toroidal-spiral particles

Area of Science:

• Materials Science
• Polymer Chemistry
• Nanotechnology

Background:

• Spherical particles have limitations in surface area and release predictability.
• Designing particles with complex internal structures is crucial for advanced applications.

Purpose of the Study:

• To describe a novel self-assembly method for creating toroidal-spiral (T-S) polymeric particles.
• To investigate the formation mechanism and control parameters of T-S particles.
• To evaluate the potential of T-S particles for controlled drug delivery.

Main Methods:

• Self-assembly of polymeric droplets (poly(ethylene glycol) diacrylate) through splashing into a miscible solution.
• UV-triggered cross-linking for solidification of T-S structures.
• Characterization of channel dimensions controlled by Weber and Reynolds numbers and viscosity ratio.
• In vitro release studies using polyphosphate as a model macromolecule.

Main Results:

• A controllable toroidal-spiral (T-S) structure was successfully formed through competitive kinetics of sedimentation, diffusion, and cross-linking.
• Channel dimensions were tunable by controlling impact and sedimentation parameters.
• Polyphosphate release kinetics were dependent on T-S particle channel dimensions.
• The self-assembly process is a single-step method under benign conditions, suitable for scale-up.

Conclusions:

• The developed self-assembly method yields polymeric particles with well-defined internal structures (T-S).
• T-S particles offer predictable release kinetics and tunable channel dimensions for drug delivery applications.
• This single-step, scalable process is promising for encapsulating delicate macromolecules.