Table 1.
Design matrix including investigated process variables with their levels
| Batch number | X1 | X2 | X3 | X4 | |
|---|---|---|---|---|---|
| 1 | 20.0 | 6.45 | 3.318 | 10.0 | |
| 2 | 36.818 | 6.45 | 5.0 | 10.0 | |
| 3 | 20.0 | 6.45 | 5.0 | 1.591 | |
| 4 | 30.0 | 4.3 | 4.0 | 15.0 | |
| 5 | 10.0 | 8.6 | 4.0 | 15.0 | |
| 6 | 20.0 | 2.834 | 5.0 | 10.0 | |
| 7 | 10.0 | 4.3 | 6.0 | 5.0 | |
| 8 | 10.0 | 4.3 | 4.0 | 5.0 | |
| 9 | 20.0 | 10.066 | 5.0 | 10.0 | |
| 10 | 20.0 | 6.45 | 5.0 | 18.409 | |
| 11 | 30.0 | 4.3 | 6.0 | 15.0 | |
| 12 | 30.0 | 8.6 | 4.0 | 5.0 | |
| 13 | 20.0 | 6.45 | 6.682 | 10.0 | |
| 14 | 20.0 | 6.45 | 5.0 | 10.0 | |
| 15 | 10.0 | 8.6 | 6.0 | 15.0 | |
| 16 | 20.0 | 6.45 | 5.0 | 10.0 | |
| 17 | 3.182 | 6.45 | 5.0 | 10.0 | |
| 18 | 30.0 | 8.6 | 6.0 | 5.0 | |
| Variable level | Lower extreme (−1.68) | Low (−1) | Medium (0) | High (1) | Higher extreme (1.68) |
| ERL loading (%, w/w) (X1) | 3.182 | 10 | 20 | 30 | 36.818 |
| Emulsifier HLB (X2) | 2.834 | 4.3 | 6.45 | 8.6 | 10.066 |
| Talc percentage (%, w/v) (X3) | 3.318 | 4 | 5 | 6 | 6.682 |
| Dispersed phase volume (mL) (X4) | 1.591 | 5 | 10 | 15 | 18.409 |
Abbreviations: HLB, hydrophilic lipophilic balance; ERL, Eudragit RLPO.