Predicting viable skin concentration: Diffusional and convective drug transport
Joshua J Calcutt1, Yuri G Anissimov2
1School of Environment and Science, Griffith University, Gold Coast, QLD 4222, Australia.
Journal of Pharmaceutical Sciences
|March 25, 2021
Summary
This study models viable skin drug transport, improving predictions for drug concentration and toxicology. The new capillary model shows faster steady-state achievement and matches experimental data for deeper skin layers.
Area of Science:
- Pharmacokinetics
- Dermal Drug Delivery
- Computational Modeling
Background:
- Viable skin drug transport significantly impacts local drug concentration, crucial for toxicology.
- Permeability enhancement techniques necessitate accurate models for predicting drug behavior.
- Existing models require refinement to capture complex transport dynamics within the skin.
Purpose of the Study:
- To develop an improved model for predicting drug transport in viable skin.
- To represent convective transport of solutes within dermal capillary loops.
- To enhance the accuracy and efficiency of skin drug transport simulations.
Main Methods:
- Expanded upon previous capillary modeling approaches.
- Incorporated convective transport of permeated solutes into capillary loops.
- Simulated drug transport dynamics within the viable epidermis and dermis.
Main Results:
- The model demonstrated that convective transport leads to a plateau in drug concentration within deeper dermal layers.
- The simulated concentration profiles align with trends observed in experimental data.
- The new model achieves steady-state five times faster than previous homogenous models.
Conclusions:
- The enhanced capillary model provides a more accurate representation of viable skin drug transport.
- The model's efficiency in reaching steady-state offers advantages for simulation speed.
- This work contributes to better prediction of drug concentration and toxicological outcomes in dermal applications.
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