Table 2.
Effects of the studied enhancers (30 mM) on the skin permeability of a model drug hydrocortisone (HC) applied at 2% w/v in 60% PG with or without the enhancer.
| Compound |
C
0
(mg/ml) |
J
SS
(µg/cm2/h) |
ER |
K
p
(×10−5 cm/h) |
C
Skin
(µg/mg) |
|---|---|---|---|---|---|
|
control (no enhancer) |
6.42 ± 0.89 | 0.03 ± 0.02 | — | 0.5 | 0.14 ± 0.05 |
| dodecanol | 6.97 ± 1.17 | 1.23 ± 0.33* | 41.0 | 17.6 | 0.33 ± 0.07 |
| DDAK | 7.00 ± 1.05 | 1.70 ± 1.19* | 56.7 | 24.3 | 0.23 ± 0.19 |
| citronellol | 7.20 ± 1.45 | 0.34 ± 0.31 | 11.3 | 4.7 | 0.45 ± 0.22 |
| C-DAK | 7.39 ± 1.35 | 1.67 ± 0.87*, ≠ | 55.7 | 22.6 | 0.24 ± 0.10 |
| geraniol | 7.79 ± 0.11 | 0.12 ± 0.02 | 4.0 | 1.5 | 0.58 ± 0.29* |
| G-DAK | 7.69 ± 0.11 | 0.39 ± 0.18≠ | 13.0 | 5.1 | 0.29 ± 0.07 |
| nerol | 7.64 ± 0.07 | 0.31 ± 0.26 | 10.3 | 4.1 | 0.20 ± 0.06 |
| N-DAK | 7.54 ± 0.19 | 1.17 ± 0.36*, ≠ | 39.0 | 15.5 | 0.31 ± 0.11 |
| farnesol | 7.25 ± 1.00 | 1.31 ± 0.45* | 43.7 | 18.1 | 0.21 ± 0.07 |
| F-DAK | 7.17 ± 0.64 | 0.72 ± 0.32≠ | 24.0 | 10.0 | 0.23 ± 0.04 |
| linalool | 6.41 ± 0.78 | 0.17 ± 0.05 | 5.7 | 2.7 | 0.25 ± 0.04 |
| L-DAK | 7.20 ± 1.14 | 0.66 ± 0.28≠ | 22.0 | 9.2 | 0.12 ± 0.02≠ |
| perillyl alcohol | 7.66 ± 0.02 | 0.07 ± 0.04 | 2.3 | 0.9 | 0.19 ± 0.05 |
| P-DAK | 7.87 ± 0.19 | 0.29 ± 0.16 | 9.7 | 3.7 | 0.30 ± 0.11 |
| menthol | 6.90 ± 0.90 | 0.16 ± 0.04 | 5.3 | 2.3 | 0.12 ± 0.03 |
| M-DAK | 7.03 ± 1.03 | 0.08 ± 0.06≠ | 2.7 | 1.1 | 0.13 ± 0.03 |
| borneol | 6.81 ± 1.18 | 0.16 ± 0.21 | 5.3 | 2.3 | 0.24 ± 0.02 |
| B-DAK | 6.96 ± 1.27 | 1.35 ± 0.60*, ≠ | 45.0 | 19.4 | 0.15 ± 0.06 |
| carveol | 7.51 ± 0.12 | 0.18 ± 0.09 | 6.0 | 2.4 | 0.19 ± 0.13 |
| Ca-DAK | 7.76 ± 0.46 | 1.14 ± 0.66* | 38.0 | 14.7 | 0.31 ± 0.15 |
| cinnamyl alcohol | 7.39 ± 0.10 | 0.08 ± 0.06 | 2.7 | 1.1 | 0.31 ± 0.30 |
| Ci-DAK | 7.92 ± 0.16 | 2.47 ± 0.44*, +, ≠ | 82.3 | 31.2 | 0.20 ± 0.08 |
Solubility of HC in the donor samples (C0), steady-state HC flux values (JSS), enhancement ratio (ER), permeability coefficient (Kp), concentration of HC in skin (CSkin). Data are presented as the means ± SD; n ≥ 3. *Statistically significant difference compared to negative control (without enhancer) at p < 0.05. +Statistically significant difference compared to DDAK (positive control) at p < 0.05. ≠Statistically significant difference compared to the respective parent terpene at p < 0.05.