Table 2.
Factors and responses in Box–Behnken design.
| Factors | Levels |
||
|---|---|---|---|
| −1 | 0 | +1 | |
| X1 PYM (mg/mL) | 2 | 4 | 6 |
| X2 CS % (w/v) | 1.8 | 2.0 | 2.2 |
| X3 GP % (w/v) | 6 | 10 | 14 |
| Responses | Constraints | ||
| | |||
| Y1% Release of PYM in 1 day | Minimize | ||
| Y2% Release of PYM in 9 days | Maximize | ||
| Y3 Rate constant k | Maximize | ||
X1 is the factor of durg loading of the peraration, X2 is the factor of CS amount, X3 is the factor of GP content. Y1 is the response of cumulative release percentage of PYM in 1 day, Y2 is the response of cumulative release percentage of PYM in 9 days, Y3 is the response of rate constant.