Table 2 Intra- and inter-assay precisions and accuracies of tramadol and its desmethylates in human plasma
Sample analytes | Theoretical value (ng/mL) | Intra-assay (n = 6) | Inter-assay (n = 6) | ||||
|---|---|---|---|---|---|---|---|
Mean ± SD (ng/mL) | Accuracy (%) | RSD (%) | Mean ± SD (ng/mL) | Accuracy (%) | RSD (%) | ||
Tramadol | 12.5 | 13.3 ± 0.71 | 106.2 | 4.8 | 12.6 ± 0.87 | 101.2 | 6.3 |
50 | 51.7 ± 4.69 | 103.3 | 8.2 | 51.8 ± 3.49 | 103.4 | 6.0 | |
200 | 203.7 ± 12.9 | 102.0 | 6.0 | 204.2 ± 10.5 | 102.2 | 4.8 | |
O-desmethylate | 800 | 819.8 ± 13.1 | 102.5 | 1.6 | 761.3 ± 39.3 | 95.1 | 4.6 |
2.5 | 2.49 ± 0.14 | 99.5 | 4.8 | 2.52 ± 0.08 | 100.8 | 2.7 | |
10 | 9.67 ± 0.38 | 96.7 | 3.6 | 9.90 ± 0.39 | 99.0 | 3.6 | |
40 | 37.4 ± 1.82 | 93.4 | 4.5 | 38.0 ± 2.14 | 94.9 | 5.1 | |
N-desmethylate | 160 | 162.8 ± 7.52 | 102.0 | 4.4 | 159.2 ± 6.46 | 99.7 | 3.8 |
2.5 | 2.23 ± 0.20 | 89.2 | 7.9 | 2.41 ± 0.09 | 96.5 | 3.2 | |
10 | 10.5 ± 0.40 | 105.2 | 3.4 | 10.2 ± 0.70 | 101.6 | 6.3 | |
40 | 37.3 ± 2.66 | 93.3 | 6.5 | 37.1 ± 1.60 | 92.7 | 4.0 | |
N,O-desmethylate | 160 | 157.0 ± 8.83 | 98.2 | 5.2 | 155.0 ± 8.12 | 96.8 | 4.8 |
2.5 | 2.32 ± 0.22 | 92.7 | 8.7 | 2.49 ± 0.17 | 99.8 | 6.2 | |
10 | 9.2 ± 0.77 | 92.5 | 7.6 | 9.77 ± 1.09 | 97.7 | 10.2 | |
40 | 41.0 ± 3.09 | 102.2 | 6.9 | 39.5 ± 2.71 | 98.8 | 6.3 | |
160 | 164.2 ± 11.1 | 102.5 | 6.2 | 155.8 ± 6.79 | 97.5 | 4.2 | |