Table 3 The stability of two analytes under different conditions (n = 5)
Analyte | Quality control concentration (µg/mL) | At 4℃ for 12 h | At room temperature for 6 h | Automatic sampler 15℃ for 24 h | Freeze-thaw for 3 cycles | Stored at -80℃ for 7 days | |||||
|---|---|---|---|---|---|---|---|---|---|---|---|
Measured value (µg/mL) | RSD (%) | Measured value (µg/mL) | RSD (%) | Measured value (µg/mL) | RSD (%) | Measured value (µg/mL) | RSD (%) | Measured value (µg/mL) | RSD (%) | ||
Colistin sulfate | 0.1 | 0.09 ± 0.01 | 8.21 | 0.10 ± 0.00 | 4.63 | 0.10 ± 0.00 | 4.47 | 0.09 ± 0.00 | 3.93 | 0.10 ± 0.00 | 4.15 |
1 | 0.93 ± 0.04 | 4.85 | 1.00 ± 0.05 | 5.11 | 0.93 ± 0.01 | 0.75 | 1.04 ± 0.04 | 3.93 | 0.98 ± 0.09 | 9.14 | |
8 | 8.23 ± 0.61 | 7.39 | 8.26 ± 0.30 | 3.64 | 8.17 ± 0.19 | 2.38 | 8.70 ± 0.54 | 6.16 | 8.30 ± 0.32 | 3.86 | |
Tigecycline | 0.05 | 0.05 ± 0.00 | 3.95 | 0.05 ± 0.00 | 5.09 | 0.05 ± 0.00 | 1.64 | 0.05 ± 0.00 | 9.09 | 0.05 ± 0.00 | 2.55 |
0.5 | 0.46 ± 0.01 | 1.99 | 0.54 ± 0.03 | 4.91 | 0.49 ± 0.03 | 5.29 | 0.52 ± 0.04 | 7.47 | 0.46 ± 0.03 | 6.05 | |
4 | 3.93 ± 0.36 | 9.19 | 4.87 ± 0.07 | 1.88 | 4.00 ± 0.26 | 6.46 | 3.82 ± 0.45 | 11.76 | 4.30 ± 0.03 | 0.72 | |