Table 1.
Mean meropenem plasma concentrations for spiked plasma samples stored at −20 °C for different durations over 1 year (n = 3 for each mean concentration reported).
| Spiked Concentration (mg/L) | Time at −20 °C (Days) | ||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 0 | 7 | 14 | 21 | 28 | 42 | 56 | 70 | 84 | 112 | 140 | 168 | 196 | 224 | 252 | 280 | 308 | 336 | 364 | |
| 0.44 (E1) | 0.46 | 0.46 | 0.46 | 0.43 | 0.43 | 0.45 | 0.45 | 0.40 | 0.43 | 0.42 | 0.42 | 0.39 | 0.35 | 0.37 | 0.36 | 0.32 | 0.30 | 0.32 | 0.32 |
| 4.38 (E2) | 4.37 | 4.47 | 4.44 | 4.18 | 4.15 | 4.26 | 4.21 | 4.02 | 4.10 | 3.97 | 3.77 | 3.74 | 3.46 | 3.55 | 3.38 | 2.90 | 2.61 | 2.86 | 2.77 |
| 17.5 (E3) | 16.4 | 17.8 | 17.0 | 15.3 | 15.5 | 16.3 | 16.0 | 14.6 | 15.0 | 14.5 | 13.8 | 12.6 | 11.6 | 12.4 | 11.4 | 10.2 | 8.8 | 10.1 | 9.4 |
| 35.1 (E4) | 33.2 | 34.5 | 33.5 | 30.2 | 29.9 | 31.8 | 31.1 | 28.5 | 29.3 | 27.9 | 26.4 | 24.5 | 21.8 | 23.0 | 20.7 | 18.9 | 16.2 | 18.3 | 16.9 |
| 52.6 (E5) | 50.3 | 52.1 | 50.6 | 46.2 | 43.5 | 47.5 | 46.1 | 41.2 | 41.9 | 42.1 | 38.1 | 35.5 | 31.0 | 32.9 | 30.4 | 26.2 | 22.4 | 26.7 | 24.2 |
| 70.1 (E6) | 67.5 | 68.7 | 67.2 | 61.2 | 59.3 | 62.8 | 62.2 | 58.5 | 58.8 | 55.8 | 50.7 | 48.6 | 43.4 | 45.8 | 41.1 | 37.1 | 31.8 | 37.2 | 32.7 |
| 87.6 (E7) | 83.3 | 86.9 | 84.2 | 75.8 | 73.7 | 79.0 | 79.0 | 72.6 | 70.2 | 69.1 | 65.5 | 61.7 | 54.7 | 57.7 | 51.3 | 47.1 | 37.5 | 45.1 | 40.6 |