Table 3. Regression Coefficient, R2, Adjusted R2, and Probability Values for the Final Model Equationa.
| regression coefficient | droplet size (Y1, nm) | PDI (Y2) | entrapment efficiency (Y3, %) |
|---|---|---|---|
| β0 | 54.27 | 0.1325 | 67.05 |
| Χ1 | –31.68 | –0.0105 | 15.57 |
| Χ2 | –8.49 | –0.0412 | 6.28 |
| Χ3 | 5.03 | 0.0081 | –1.93 |
| Χ12 | 12.71 | 0.0165 | –7.03 |
| Χ22 | 6.51 | 0.0476 | –1.98 |
| Χ32 | 2.4 | 0.0001 | 0.2349 |
| Χ12 | 0.58 | –0.0581 | –3.96 |
| Χ13 | –0.3375 | –0.0344 | –0.0788 |
| Χ23 | –0.715 | 0.0369 | 0.0612 |
| R2 | 0.9507 | 0.8947 | 0.9977 |
| adjusted R2 | 0.9063 | 0.7999 | 0.9956 |
| regression (p-value) | <0.0001b | 0.0008b | <0.0001b |
a
β0 is a constant; X1, X2, and X3 are the estimated regression coefficients for the main linear effects; X12, X22, and X32 are the estimated regression coefficients for the quadratic effects; X12, X13, and X23 are the estimated regression coefficients for the interaction effects. X1: surfactant-to-oil ratio (SOR), X2: the ratio of high hydrophilic–lipophilic balance (HLB) surfactant to low HLB surfactant (HLR), X3: the effect of PEG-40 and PEG-60 hydrogenated castor oil.
b
Indicates a significant term (p < 0.05).