Effect of organic solvents on normal human stratum corneum: evaluation by the corneoxenometry bioassay.
BACKGROUND
Organic solvents alter the stratum corneum structure and barrier function.


OBJECTIVE
To measure the effect of various solvents upon human stratum corneum using the ex vivo corneoxenometry bioassay which is a variant of corneosurfametry.


METHODS
Corneoxenometry entails collection of human stratum corneum by cyanoacrylate. The material is immersed in organic solvents for periods ranging from 1 to 120 min. After staining the samples with a toluidine blue-basic fuchsin solution, the color is measured using reflectance colorimetry. Solvent aggressivity to the stratum corneum correlates with the color darkening of the samples.


RESULTS
The least aggressive solvent was hexane, followed by ethanol, methanol, hexane-ethanol, chloroform, chloroform-methanol and hexane-methanol. The influence of contact time between solvents and the stratum corneum showed a logarithmic pattern which varied according to the solvent.


CONCLUSIONS
Data are in line with previous experiments conducted in vivo and in vitro, thus indicating the predictive value of corneoxenometry. Such a bioassay may avoid hazards of some in vivo human testings.
Goffin
V
V
Belgian SSTC Research Center 5596, Department of Dermatopathology, University of Liège, Belgium.
Letawe
C
C
Piérard
G E
GE
D000438:Alcohols / Q000494:pharmacology*; D001681:Biological Assay; D002725:Chloroform / Q000494:pharmacology; D003124:Colorimetry / Q000379:methods; D004396:Coloring Agents; D003487:Cyanoacrylates; D004817:Epidermis / Q000187:drug effects* / Q000473:pathology; D000431:Ethanol / Q000494:pharmacology; D005069:Evaluation Studies as Topic; D006586:Hexanes / Q000494:pharmacology; D006801:Humans; D006838:Hydrocarbons / Q000494:pharmacology*; D007101:Immersion; D016014:Linear Models; D000432:Methanol / Q000494:pharmacology; D012044:Regression Analysis; D012394:Rosaniline Dyes; D012997:Solvents / Q000494:pharmacology*; D013997:Time Factors; D014048:Tolonium Chloride; D014870:Water Loss, Insensible / Q000187:drug effects
D000438:Alcohols; D004396:Coloring Agents; D003487:Cyanoacrylates; D006586:Hexanes; D006838:Hydrocarbons; D012394:Rosaniline Dyes; D012997:Solvents; D014048:Tolonium Chloride; D000431:Ethanol; C025485:basic fuchsin; D002725:Chloroform; D000432:Methanol