Table 3.
Independent and dependent variables in the Box-Behnken experimental design.
| Independent variables | Levels | ||
|---|---|---|---|
| PLGA %, (X1) | 20 | 30 | 40 |
| PEG %, (X2) | 0 | 5 | 10 |
| BB % in NMP, (X3) | 10 | 15 | 20 |
| Dependent variables | Constraints | ||
| Low | High | Target | |
| Initial burst after 2 hours, % (Y1) | 412.03 | 1020.24 | Minimize |
| Initial burst after 24 hours, % (Y2) | 806.46 | 1520.53 | Minimize |
| Cumulative release after 28 days, % (Y3) | 1803.92 | 3039.05 | Maximize |
Abbreviations: PLGA, poly (D, L-lactide-co-glycolide); PEG, polyethylene glycol; BB, benzyl benzoate; NMP, N-methyl-2-pyrrolidone.