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Reverse Iontophoresis: Noninvasive Assessment of Topical Drug Bioavailability
Kieran Moore1, Sébastien Grégoire2, Joan Eilstein2
1Department of Life Sciences, University of Bath, Claverton Down, Bath BA2 7AY, U.K.
Molecular Pharmaceutics
|December 7, 2023
Summary
Reverse iontophoresis (RI) offers a noninvasive method to assess drug bioavailability in skin. This technique successfully extracted salicylic acid and nicotine, demonstrating its potential for topical drug monitoring.
Area of Science:
- Dermatology
- Pharmacokinetics
- Analytical Chemistry
Background:
- Assessing topical drug disposition in skin is challenging.
- Reverse iontophoresis (RI) can extract charged molecules noninvasively.
- RI may offer a method for local drug bioavailability assessment.
Purpose of the Study:
- To evaluate reverse iontophoresis (RI) as a noninvasive method for assessing drug disposition in skin.
- To compare RI extraction with traditional methods for salicylic acid and nicotine.
- To validate RI predictions using mathematical modeling.
Main Methods:
- In vitro and in vivo studies using porcine and human skin.
- Passive and RI extraction of salicylic acid and nicotine.
- Quantification of drug amounts in stratum corneum and viable tissue.
- Mathematical modeling of drug extraction profiles.
Main Results:
- RI extraction was significantly higher than passive extraction for both drugs, in vitro and in vivo.
- Mathematical modeling accurately predicted drug amounts in skin layers.
- In vitro predictions of drug disposition correlated well with experimental results.
- In vivo results showed good agreement with in vitro predictions.
Conclusions:
- Reverse iontophoresis is a promising noninvasive technique for assessing topical drug bioavailability.
- RI allows for the determination of key pharmacokinetic parameters in the skin.
- This method provides a proof-of-concept for improved topical drug monitoring.
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