Table 7.
Evaluation data of the stability study of the selected microemulsion formulation (F3) at room temperature (25 °C) and refrigeration temperature (4 °C).
| Parameters ≠ | Temp. | Time (month) | ||||||
|---|---|---|---|---|---|---|---|---|
| 0 | 1 | 2 | 3 | 4 | 5 | 6 | ||
|
Droplet size
(nm) |
25 °C | 220 ± 3.8 | 226 ± 3.7 | 231 ± 5.9 | 224 ± 3.5 | 196 ± 1.6 | 210 ± 1.5 | 224 ± 2 |
| 4 °C | 220 ± 3.8 | 232 ± 2.6 | 250 * ± 3.4 | 283 ** ± 2 | 290 ** ± 1.5 | 297 ** ± 2.5 | 310 ** ± 3 | |
| PDI | 25 °C | 0.22 ± 0.02 | 0.3 ± 0.01 | 0.32 ± 0.02 | 0.35 ± 0.04 | 0.33 ± 0.05 | 0.37 ± 0.03 | 0.4 ± 0.02 |
| 4 °C | 0.22 ± 0.02 | 0.35 ± 0.04 | 0.412 ± 0.02 | 0.52 ± 0.03 | 0.51 ± 0.03 | 0.55 ± 0.01 | 0.5 ± 0.03 | |
| Zeta potential (mV) | 25 °C | −25 ± 1.1 | −24.5 ± 2.5 | −23.1 ± 1.5 | −22.3 ± 2 | −22 ± 2.6 | −21.5 ± 1 | −21 ± 2 |
| 4 °C | −25 ± 1.1 | −24.06 ± 2 | −21.3 ± 1.5 | −19.29 ± 3 | −18 ± 2.2 | 18.5 ± 2.5 | 17.9 ± 1.6 | |
| pH | 25 °C | 5.39 ± 0.02 | 5.46 ± 0.04 | 5.5 ± 0.05 | 5.6 ± 0.04 | 5.75 ± 0.03 | 5.81 ± 0.02 | 5.9 ± 0.02 |
| 4 °C | 5.39 ± 0.03 | 5.45 ± 0.05 | 5.55 ± 0.07 | 5.6 ± 0.04 | 5.71 ± 0.02 | 5.77 ± 0.03 | 5.8 ± 0.02 | |
| Appearance | 25 °C | Translucent | Translucent | Translucent | Translucent | Translucent | Translucent | Translucent |
| 4 °C | Translucent | Translucent | Slight turbidity | Slight turbidity | Turbid | Turbid | Turbid | |
≠ Data were expressed as mean value ± SD (n = 3). * Significantly differ from initial value (p < 0.05); ** highly significant difference from initial value (p ˂ 0.01).