Table 2.
Matrix of experimental design.
| Formulation code | Run order | X1 (%) | X2 (mM) | X3(mM) | X4 | X5 |
|---|---|---|---|---|---|---|
| N1 | 16 | 0 | 5 | 0 | 1 | −80 °C |
| N2 | 8 | 0 | 10 | 2.5 | 1 | −20 °C |
| N3 | 7 | 0 | 15 | 5 | 1 | None |
| N4 | 20 | 2.5 | 5 | 0 | 1 | −20 °C |
| N5 | 9 | 2.5 | 10 | 2.5 | 1 | None |
| N6 | 11 | 2.5 | 15 | 5 | 1 | −80 °C |
| N7 | 15 | 5 | 5 | 2.5 | 1 | −80 °C |
| N8 | 14 | 5 | 10 | 5 | 1 | −20 °C |
| N9 | 2 | 5 | 15 | 0 | 1 | None |
| N10 | 19 | 0 | 5 | 5 | 3 | None |
| N11 | 6 | 0 | 10 | 0 | 3 | −80 °C |
| N12 | 13 | 0 | 15 | 2.5 | 3 | −20 °C |
| N13 | 12 | 2.5 | 5 | 2.5 | 3 | None |
| N14 | 4 | 2.5 | 10 | 5 | 3 | −80 °C |
| N15 | 18 | 2.5 | 15 | 0 | 3 | −20 °C |
| N16 | 1 | 5 | 5 | 5 | 3 | −20 °C |
| N17 | 5 | 5 | 10 | 0 | 3 | None |
| N18 | 17 | 5 | 15 | 2.5 | 3 | −80 °C |
| N19 | 10 | 2.5 | 10 | 2.5 | 2 | None |
| N20 | 21 | 2.5 | 10 | 2.5 | 2 | None |
| N21 | 3 | 2.5 | 10 | 2.5 | 2 | None |
X1, PEG proportion (%); X2, cholesterol concentration (mM); X3, the cryoprotectant to phospholipids molar ratio; X3, the number of extrusions through 100 nm polycarbonate membranes; X5, the freezing conditions prior lyophilization.