[Non-equilibrium properties of drug permeation through stratum corneum in vitro].
OBJECTIVE
To illustrate the non-equilibrium properties of drug permeation through stratum corneum (SC) to provide theory and method for transdermal drug delivery.


METHODS
The system of side-by-side permeation chambers in vitro was isolated, thus conditions for equilibrium state were decided. And a network thermodynamic model was established. Non-equilibrium and leakage experiments were completed with which tinidazole was pattern drug.


RESULTS
The properties of non-equilibrium including: long term to reach equilibrium state; delay-start of the permeation; uncertainty of initial drug permeable flux. The properties of leakage including: degression of drug permeable flux; changeability of permeation time constant.


CONCLUSIONS
The permeation cell is believed to be a non-linear and time variable system.
Bao
Jia-li
JL
College of Medicine, Zhejiang University, Hangzhou 310006, China. baojl@zju.edu.cn
Wang
Hong
H
Ge
Ji-guang
JG
D000279:Administration, Cutaneous; D018274:Electroporation; D004817:Epidermis / Q000378:metabolism*; D006801:Humans; D066298:In Vitro Techniques; D010539:Permeability; D014011:Tinidazole / Q000008:administration & dosage / Q000493:pharmacokinetics*
D014011:Tinidazole