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Algorithms for skin permeability using hydrogen bond descriptors: the problem of steroids
M H Abraham1, F Martins, R C Mitchell
1Department of Chemistry, University College London, UK.
The Journal of Pharmacy and Pharmacology
|November 5, 1997
Summary
This study developed a new algorithm using hydrogen bond descriptors to predict skin permeability (Kp) for non-steroids. The Abraham equation-based model shows promise for estimating compound permeation through the stratum corneum.
Area of Science:
- Pharmacokinetics and Drug Delivery
- Computational Chemistry
- Dermal Permeation Science
Background:
- Algorithms predicting skin permeation often utilize hydrogen bond descriptors.
- Existing models have varying success rates for different compound classes.
Purpose of the Study:
- To develop a novel, robust algorithm for predicting skin permeability coefficients (Kp) of non-steroidal compounds.
- To correlate existing skin permeability data using the Abraham solvation equation.
Main Methods:
- Correlated non-steroidal skin permeability coefficients (Kp) using the Abraham equation.
- Employed solute descriptors: excess molar refraction (R2), dipolarity/polarizability (π2H), hydrogen-bond acidity/basicity (σα2H, σβ2H), and McGowan characteristic volume (Vx).
Main Results:
- A new predictive algorithm for log Kp was established based on the Abraham equation.
- The developed algorithm demonstrated reasonable predictive accuracy for steroid log Kp values from Johnson et al.
- The algorithm showed lower predictive performance for steroid log Kp values reported by Scheuplein.
Conclusions:
- The developed Abraham equation-based algorithm offers a new approach for predicting non-steroidal skin permeation.
- The model's applicability may vary depending on the source and nature of the permeability data.
- Further validation is recommended for diverse compound sets and data sources.
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