Tab. 3.
Method characteristics
| Analyte | Zileuton |
| Internal Standard | Zileuton D4 |
| Method Description | Liquid-liquid extraction |
| Regression Model | Linear regression with 1/Conc2 weighing |
| Analysis method | Peak area ratios |
| Limit of Quantification | 50.5 ng/ml |
| Selectivity | No interference from the endogenous matrix components |
| Recovery of analyte | 84.2% |
| Recovery of internal standard | 87.6% |
| Linearity Range | 50.5 to 10012.7 ng/ml |
| LLOQQC: 50.6 ng/ml | |
| LQC: 148.8 ng/ml | |
| Quality Controls concentrations | MQC: 4510.4 ng/ml |
| HQC: 7517.4 ng/ml | |
| QC interday accuracy range | 102.1 to 107.0% |
| QC interday precision range | 2.9 to 7.7 |
| Benchtop stability | 18 h at room temperature |
| Freeze-Thaw stability | 3 cycles |
| Auto injector stability | 38h |
| Long-term stability | 74 days at -70°C |
| Stock solution stability | 9 days |
| Stock dilution stability | 26 h |
| Dilution integrity | 1/2 and 1/4 |
| Re-injection Reproducibility | One time |