| Nominal | Unprocessed | Processed | Freeze-Thaw | ||||
| Level | 24 hrs | 8 wks | 24 hrs | 48 hrs | Cycle | ||
| (μg/ml) | RT | −20˚C | RT | −20˚C | 1 | 2 | 3 |
| Colistin A |
|
|
|
|
|
|
|
| 0.05 | 91 | 104 | 99 | 106 | 117 | 118 | 113 |
| 0.15 | 87 | 101 | 98 | 105 | 100 | 103 | 108 |
| 9.0 | 104 | 90 | 106 | 111 | 110 | 109 | 107 |
| Colistin B |
|
|
|
|
|
|
|
| 0.05 | 96 | 107 | 92 | 100 | 114 | 116 | 113 |
| 0.15 | 92 | 95 | 107 | 107 | 107 | 101 | 106 |
| 9.0 | 97 | 94 | 100 | 91 | 110 | 102 | 104 |