Table 2.
Transdermal delivery, lag time, flux, permeability coefficient, and steady-state plasma concentration of in vitro permeation of MTX though dermatomed human cadaver skin (mean ± SD, n = 4).
| Group | Q24a (µg/sq·cm) | Lag Time b (h) | Jss (µg/sq·cm/h) c |
Kp (cm/h) d × 10−4 |
Css (ng/mL) e |
|---|---|---|---|---|---|
| Passive | 0.00 ± 0.00 | 0.00 ± 0.00 | 0.00 ± 0.00 | 0.00 ± 0.00 | 0.00 ± 0.00 |
| Anodal ITP | 4.74 ± 0.62 | 3.57 ± 1.07 | 0.05 ± 0.03 | 0.26 ± 0.14 | 0.28 ± 0.15 |
| Cathodal ITP | 0.54 ± 0.07 | 0.20 ± 0.05 | 0.01 ± 0.00 | 0.07 ± 0.02 | 0.08 ± 0.02 |
| LFS | 161.92 ± 30.06 | −5.09 ± 1.03 | 6.81 ± 1.31 | 34.04 ± 6.55 | 36.92 ± 7.11 |
| Anodal ITP + LFS | 333.10 ± 37.01 | 11.83 ± 10.77 | 13.42 ± 1.95 | 67.08 ± 9.73 | 72.77 ± 10.55 |
| Cathodal ITP + LFS | 178.30 ± 23.79 | −15.93 ± 16.74 | 8.03 ± 1.17 | 40.14 ± 5.85 | 43.54 ± 6.35 |
a Cumulative amount of MTX (Q24) permeated through a unit of diffusion area in 24 h. b Lag time—calculated as the x-intercept of the linear portion of the permeation curve (R2 > 0.90). c Steady-state flux (J)—calculated from the linear slope of the permeation curve. d Permeability coefficient (Kp)—calculated using an equation: Kp = J/CA, where Kp is the permeability coefficient (cm/h), J is the steady-state flux (µg/h), C is the MTX concentration in the donor (µg/mL), and A is the permeation area (0.64 sq.cm). e Steady-state plasma concentration (Css)—calculated using an equation: Css = (A × Jss)/Cl, where Css is the steady-state plasma concentration (µg/mL), A is the permeation area of skin (0.64 sq·cm), Jss is the steady-state flux (µg/sq·cm/h), and Cl is the clearance of MTX from the body.