Table 3.
Storage conditions | Nominal concentration (ng/mL) | Calculated concentration (ng/mL) | RSD (%) | RE (%) |
---|---|---|---|---|
Room temperature for 4 h | 3.0 | 3.04±0.10 | 4.72 | 1.44 |
30.0 | 29.8±0.5 | 1.51 | −0.78 | |
240.0 | 243.0±8.1 | 3.35 | 1.40 | |
Processed QC samples under autosampler conditions | 3.0 | 2.95±0.10 | 2.76 | −1.56 |
30.0 | 29.9±0.9 | 2.85 | −0.44 | |
240.0 | 241.0±11.7 | 4.85 | 0.30 | |
Three freeze/thaw cycles | 3.0 | 2.99±0.10 | 1.84 | −0.22 |
30.0 | 29.7±1.3 | 4.38 | −0.89 | |
240.0 | 239.0±4.5 | 1.89 | −6.30 | |
Storage at −80 °C for 75 days | 3.0 | 2.97±0.10 | 2.99 | −0.22 |
30.0 | 29.8±0.3 | 1.01 | −0.67 | |
240.0 | 239.0±9.8 | 4.12 | −0.40 |