Table 3. Precision and accuracy of coumarin (COU), 7-hydroxycoumarin (7-HCOU), 6-methylcoumarin (6-MC), o-coumaric acid (OCA), kaurenoic acid (KAU), isoferulic acid (ISOF) and prednisone (PRED) obtained in human plasma by HPLC-MS/MS experiments.
| Compounds | Quality Control level | Accuracy | Precision | ||||
|---|---|---|---|---|---|---|---|
| Standard concentration(ng/mL) | Intra-day RE% | Inter-day RE% | Intra-day (RSD%) | Inter-day (RSD%) | |||
| Positive ion mode | COU | LLOQ | 10.0 | -10.09 | -7.56 | 5.91 | 5.05 |
| LQC | 50.0 | -1.71 | 1.15 | 2.72 | 2.98 | ||
| MQC | 500.0 | -2.44 | 2.66 | 2.75 | 2.93 | ||
| HQC | 1250.0 | -7.16 | -4.72 | 3.91 | 3.93 | ||
| DQC | 1600.0 | -1.66 | -1.84 | 2.90 | 1.97 | ||
| 7-HCOU | LLOQ | 7.5 | -1.03 | -0.88 | 9.95 | 8.47 | |
| LQC | 12.5 | 9.88 | 2.57 | 4.34 | 6.76 | ||
| MQC | 100.0 | -3.82 | 0.92 | 3.50 | 4.37 | ||
| HQC | 750.0 | -1.37 | -1.53 | 3.56 | 5.19 | ||
| DQC | 1100.0 | -1.44 | 0.35 | 3.31 | 4.19 | ||
| 6-MC* | - | 500.0 | 5.31 | 0.96 | 3.66 | 6.09 | |
| Negative ion mode | OCA | LLOQ | 10.0 | 0.29 | -3.56 | 8.96 | 10.14 |
| LQC | 25.0 | -3.89 | -0.27 | 5.64 | 4.77 | ||
| MQC | 100.0 | -2.56 | 1.02 | 3.99 | 3.86 | ||
| HQC | 750.0 | -1.98 | -0.81 | 4.17 | 2.91 | ||
| DQC | 1100.0 | 2.11 | -0.43 | 3.38 | 4.82 | ||
| KAU | LLOQ | 5.0 | -8.15 | -3.51 | 9.96 | 8.79 | |
| LQC | 10.0 | -3.64 | -3.87 | 4.14 | 6.07 | ||
| MQC | 75.0 | -1.60 | -2.01 | 3.27 | 2.89 | ||
| HQC | 500.0 | 2.26 | 1.55 | 4.44 | 3.75 | ||
| DQC | 850.0 | -2.79 | -2.12 | 2.97 | 3.07 | ||
| ISOF* | - | 1000.0 | -0.81 | 1.94 | 2.87 | 3.66 | |
| PRED* | - | 500.0 | 0.76 | 0.30 | 3.22 | 3.94 | |
Data: LLOQ: lower limit of quantification; LQC: low quality control; MQC: medium quality control; HQC: high quality control; DQC: dilution quality control; Intra-day analysis, n = 8; Inter-day analysis, n = 24; RE%: relative error; RSD%: relative standard deviation; *internal standard