INFLUENCE OF DEPLETION ON PERCUTANEOUS ABSORPTION 24! B C B E F 0 6 12 18 24 30 TIME (HR) Figure 2. Amount penetrated into the sink compartment as a function of time for various donor volumes. K = 0.6 hr -•. Ki/K_ I = 10. (A) 1,10 mi. (B) 0.1 mi. (C) 0.032 mi. (D) 0.01 mi. (E) 0.0032 mi. (F) 0.001 mi. lOO 8o 20 0 0 20 40 60 80 100 OlST^NCE Figure 3. Compartmental concentration as a function of distance from the donor (expressed as per cent of stratum corneum thickness). Rate constants as for Figure 2. Donor volume = 10 mi. [•, 2 hours. A, 5 hours. V, 20 hours.

242 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS z r• Z W U Z U 8O 8O 4O 2O 0 5 12 •8 24 30 TIME (HR) Figure 4. Concentration (mg/ml) in stratum corncum compartments as a function of time. Compartments are numbered in order with the lowest number being the dosest to the donor. Rate constants as For Figure 2. Donor volume = 10 ml. 8O Z o 40 Z Z 20 0 I I I I I I I I-- i I 0 20 40 60 BO 100 DISTANCE Figure 5. Compartmental concentration as a function of distance from the donor (expressed as per cent of stratum corneum thickness). Rate constants as for Figure 2. Donor volume = 0.0032 mi. [•, 2 hours. A, 5 hours. V, 20 hours.