Table 4.
The kinetic of sulfanilamide release from p(NIPAM) hydrogels.
| Kinetic Model | Parameter | pH = 2.2 | pH = 7.4 | ||||||
|---|---|---|---|---|---|---|---|---|---|
| 1% | 1.5% | 2% | 2.5% | 1% | 1.5% | 2% | 2.5% | ||
| Higuchi F = kH ∙ t1/2 |
kH | 7.290 | 9.075 | 7.055 | 7.507 | 6.974 | 9.116 | 7.507 | 6.786 |
| R2 | 0.714 | 0.488 | 0.794 | 0.736 | 0.782 | 0.634 | 0.742 | 0.882 | |
| AIC | 28.418 | 30.737 | 26.540 | 27.944 | 25.975 | 29.600 | 26.974 | 23.841 | |
| Korsmeyer–Peppas F = kKP ∙ tn |
kKP | 53.229 | 56.767 | 34.855 | 44.929 | 26.621 | 42.202 | 28.375 | 20.528 |
| n | 0.041 | 0.077 | 0.132 | 0.087 | 0.192 | 0.147 | 0.194 | 0.246 | |
| R2 | 0.993 | 0.848 | 0.983 | 0.980 | 0.935 | 0.865 | 0.898 | 0.970 | |
| AIC | 15.681 | 27.868 | 18.652 | 19.635 | 23.147 | 27.601 | 25.249 | 20.314 | |
kH: the constant of release at Higuchi model; R2: coefficient of determination; AIC: Akaike’s information criterion; F: the fraction of released drug in the function of time t; kKP: the constant of release at Korsmeyer-Peppas model that takes into account structural and geometrical characteristics of the dosage form; n: the exponent of release/diffusion [54,55].