TABLE 3.
Investigated process factors of I-optimal RSM design. Given are the simplified names (see Table 1), units, and each a lowest, and highest factor level limit, respectively. Please note, the categoric factor ‘method’ was introduced as combination of the two previous factors describing possible impregnation methods, i.e., preceding pre-wetting step, or addition of EtOH to the impregnation solution.
| Factor | Name | Units | Type | Lower limit | Upper limit |
|---|---|---|---|---|---|
| A | BSA | g L−1 | numeric | 1.0 | 18.4 |
| B | time | min | numeric | 0.1 | 12.4 |
| C | dose | kGy | numeric | 20 | 234 |
| D | method | — | categoric | 1-step (EtOH) | 2-steps (pre-wetting) |