Table 2. Inter-lab and intra-lab validation of Method 1 for quantification of flunixin and 5-hydroxy flunixin in milk
| Target | Linearity (r2) | Fortification (μg/kg) | Inter-lab | Inter-lab | LOD (μg/kg) | LOQ (μg/kg) |
| Recovery (%) | CV (%) | Recovery (%) | CV (%) |
| Lab A | Lab B |
| Flunixin | 0.9943 | 10 | 112 | 3.7 | 85.0 | 74.5 | 21 | 4 | 15 |
| 20 | 115 | 5.4 | 82.4 | 76.1 | 22 |
| 40 | 110 | 2.2 | 79.8 | 94.0 | 8.9 |
| 5-Hydroxy flunixin | 0.9979 | 10 | 108 | 3.1 | 82.7 | 73.6 | 20 | 5 | 15 |
| 20 | 99.6 | 5.9 | 82.7 | 71.2 | 18 |
| 40 | 94.0 | 9.3 | 77.4 | 74.8 | 14 |
CV, coefficient of variation; LOD, limits of detection; LOQ, limits of quantification.