Table 5 Stability of the analytes (n = 3)
Compound | Concentration (ng/mL) | Autosampler stability (%) (10 ℃ for 4 days) | Bench-top stability (%) | Long-term stability (%) | |
|---|---|---|---|---|---|
(room temp. for 24 h) | (4 ℃ for 7 days) | (4℃ for 21 days) | |||
EtG | 15.0 | − 4.0 | 0.3 | 0.7 | − 2.7 |
800.0 | 3.1 | 9.6 | 8.3 | − 1.9 | |
NTX | 3.0 | − 3.3 | 4.5 | − 0.4 | − 6.0 |
80.0 | 0.1 | 2.0 | 0.7 | − 2.1 | |
6βNTX | 15.0 | − 4.3 | − 7.3 | − 4.9 | − 4.0 |
800.0 | − 0.7 | 8.0 | 9.6 | 3.5 | |
CDP | 15.0 | − 2.8 | 3.9 | 3.9 | 1.0 |
800.0 | 2.5 | 0.4 | 4.3 | − 5.8 | |
norCDP | 15.0 | 2.2 | − 5.8 | − 2.1 | 0.0 |
800.0 | 3.4 | − 0.1 | 5.0 | − 4.5 | |