Table 3.
Droplet size and saturated solubilities of sildenafil citrate in different microemulsion systems at room temperature.
| Composition of Microemulsion Systems (%) | Droplet Size (nm) | Solubility of Sildenafil Citrate (mg/mL) | ||||
|---|---|---|---|---|---|---|
| Isopropyl Myristate | Tween 80/PEG 400 | Oleic Acid | Tween 80/Propylene Glycol | Purified Water | ||
| 30 | 25:25 (1:1) | - | - | 20 | 35 ± 10 | 72 ± 12 |
| 20 | 20:40 (1:2) | - | - | 20 | 62 ± 12 | 58 ± 4 |
| 20 | 16:49 (1:3) | - | - | 15 | 45 ± 8 | 82 ± 16 |
| 30 | 40:20 (2:1) | - | - | 10 | 30 ± 6 | 122 ± 28 |
| 20 | 49:16 (3:1) | - | - | 15 | 110 ± 20 | 108 ± 14 |
| - | - | 15 | 37.5:37.5 (1:1) | 10 | 593 ± 126 | 108 ± 12 |
| - | - | 10 | 25:50 (1:2) | 15 | 385 ± 81 | 103 ± 9 |
| - | - | 8 | 18:54 (1:3) | 20 | 600 ± 125 | 95 ± 24 |
| - | - | 22 | 43:22 (2:1) | 13 | 320 ± 45 | 128 ± 8 |
| - | - | 15 | 52.5:17.5 (3:1) | 15 | 465 ± 114 | 112 ± 16 |
Droplet size and solubility values are the mean ± SD, n = 3.