Solubility and Transdermal Permeation Properties of a Dehydroepiandrosterone Cyclodextrin Complex from Hydrophilic and Lipophilic Vehicles

Figures & data

TABLE 1 DHEA solubilities in the vehicles at 25°C

	Paraffin oil	Microemulsion	Distilled water
DHEA (μ g/ml)	2.01 · 10^2 sd 5.60	8.97 · 10^2 sd 2.13 · 10^1	6.50 sd 0.3
c-DHEA (μ g/ml of DHEA equivalent)	3.98 · 10^2 sd 1.13 · 10^1	9.76 · 10^3 sd 1.16 · 10^2	20.6 sd 0.9

*Ref. mean value of three experiments sd.

FIG. 1. Permeation profiles of DHEA from the tested suspensions. The continuous lines are the permeation profiles of c-DHEA, the discontinuous are the ones of DHEA.

TABLE 2 DHEA permeation parameters from the vehicles

	Js (μg/cm^2 h^−1)	Permeability coefficient (Kp) (cm/h)	Lag time (hr)	Diffusion coefficient (D) (cm^2/h)	Partition parameter (P) skin/vehicle
DHEA in paraffin oil	34.9 sd 2.8	1.74 · 10^−1 sd 1.41 · 10^−2	2.112 sd 6.75 · 10^−1	8.45 · 10^−4 sd 2.73 · 10^−4	21.73 sd 5.35
c-DHEA in paraffin oil	32.8 sd 3.1	8.26 · 10^−2 sd 7.91 · 10^−3	1.595 sd 4.793 · 10^−1	9.07 · 10^−4 sd 1.21 · 10^−4	5.93 sd 2.30
DHEA in microemulsion	9.7 sd 0.3	1.10 · 10^−2 sd 3.7 · 10^−4	2.617 sd 4.96 · 10^−1	6.51 · 10^−4 sd 1.13 · 10^−4	1.72 sd 3.80 · 10^−1
c-DHEA in microemulsion	43.0 sd 9.4	4.32 · 10^−3 sd 9.5 · 10^−4	3.819 sd 4.91 · 10^−1	4.41 · 10^−4 sd 5.87 · 10^−5	1.01 sd 3.49 · 10^−1
DHEA in purified water	7.3 sd 2.3	1.12 sd 0.50	5.39 sd 2.15	3.13 · 10^−4 sd 1.26 · 10^−4	358.11 sd 129.7
c-DHEA in purified water	13.66 sd 3.3	d0.66 sd 0.19	5.17 sd 1.21	3.22 · 10^−4 sd 7.50 · 10^−5	204.92 sd 28.2

*Ref. mean value of 6 experiments sd.

FIG. 2. Correlation between partiton coefficient P as a function of the solubility of the drug in different vehicles (of the complexed and pure forms).