Effect of pressure on in vitro percutaneous absorption of caffeine.
The effect of increased pressure, which is a mechanical property of massage, was investigated on the percutaneous absorption of an amphiphilic compound (caffeine) in vitro on Franz diffusion cells, using excised human skin. 50 microliters of either a 320 micrograms/ml or a 15 mg/ml acetone solution of caffeine were pipetted onto the surface of each skin sample, which represented caffeine skin deposits of 5 micrograms/cm2 and 240 micrograms/cm2 respectively. During each experiment, a pressure device delivering 0.25 bar over the atmospheric pressure was applied for the first 30 min on half of the cells. At 2, 4, 6, 8, 12 and 24 h the aqueous dermal bathing solution, containing 14 g/l albumin, was removed and chromatographed. With the applied dose of 5 micrograms/cm2 no statistical difference was found between the cumulated absorbed amount under atmospheric pressure and increased pressure. On the other hand, with the applied dose of 240 micrograms/cm2, the permeation of caffeine was 1.8 times higher under increased pressure than the permeation under atmospheric pressure (p < 0.05). This enhancing effect of increased pressure was probably connected to either an improved transappendageal route during the percutaneous absorption process or a higher stratum corneum filling-up.
Treffel
P
P
Department of Dermatology, Saint-Jacques Hospital, Besançon, France.
Panisset
F
F
Humbert
P
P
Remoussenard
O
O
Bechtel
Y
Y
Agache
P
P
D000328:Adult; D002110:Caffeine / Q000493:pharmacokinetics*; D005260:Female; D006801:Humans; D066298:In Vitro Techniques; D008875:Middle Aged; D011312:Pressure; D012869:Skin Absorption
D002110:Caffeine