Transdermal Drug Delivery: Determining Permeation Parameters Using Tape Stripping and Numerical Modeling

Area of Science:

• Pharmacology
• Biomedical Engineering
• Materials Science

Background:

• Transdermal drug delivery (TDD) systems involve complex, multi-layered structures to control drug release and skin interaction.
• Understanding drug permeation parameters through skin layers is crucial for optimizing TDD system efficacy.
• Existing models often require refinement to accurately capture the nuances of drug diffusion across biological barriers.

Purpose of the Study:

• To investigate and quantify the parameters governing drug permeation through skin layers within a transdermal drug delivery system.
• To develop and validate a multi-layered numerical model for simulating drug diffusion.
• To assess the correlation between experimental data and numerical predictions for skin permeability.

Main Methods:

• Experimental diffusion studies using porcine skin in a Franz diffusion cell.
• Tape stripping technique to quantify drug concentration within the stratum corneum.
• Development of a multi-layered numerical model based on Fickian diffusion principles.
• Determination of unknown skin permeability parameters, including interlayer partition and mass transfer coefficients.

Main Results:

• A significant correlation was observed between the results obtained from numerical modeling and experimental data.
• The numerical model accurately represents partition and mass transfer effects at the interlayer boundary.
• Key parameters defining skin permeability, such as partition coefficients and mass transfer coefficients, were determined.
• Tape stripping provided essential quantitative data for validating the diffusion model.

Conclusions:

• Numerical modeling is indispensable for a comprehensive understanding of drug diffusion characteristics in transdermal systems.
• The developed multi-layered model effectively captures the complex interactions governing drug permeation.
• Accurate characterization of skin permeability parameters is achievable through integrated experimental and numerical approaches.
• This work provides a robust framework for the design and optimization of future transdermal drug delivery systems.