A mathematical model for predicting controlled release of bioactive agents from composite fiber structures

Area of Science:

• Biomaterials Science
• Polymer Science
• Biomedical Engineering

Background:

• Core/shell fibers offer tunable mechanical properties and controlled release for biomedical applications.
• Existing models may not fully capture the complexities of bioactive agent release from degrading fibrous structures.

Purpose of the Study:

• To develop and validate a mathematical model for predicting bioactive agent release from core/shell fibers.
• To investigate the influence of shell degradation and diffusion dynamics on release profiles.
• To assess the model's predictive accuracy using in vitro data.

Main Methods:

• Developed a mathematical model based on Fick's second law of diffusion.
• Incorporated first-order degradation kinetics for the porous shell.
• Included a time-dependent diffusion coefficient influenced by polymer degradation.
• Evaluated porosity, tortuosity, and polymer concentration factors.

Main Results:

• The model demonstrated strong correlation with in vitro release data, achieving a mean error below 2.2% in most cases.
• Successfully predicted protein release profiles from fibers with varying shell molecular weights.
• Accurately predicted the release of proteins with different molecular weights.

Conclusions:

• The developed mathematical model provides a reliable tool for simulating bioactive agent release from core/shell fibers.
• This model has significant potential for optimizing fibrous systems in tissue regeneration and other biomedical applications.
• The model's ability to account for degradation and diffusion dynamics enhances its utility for designing advanced biomaterials.