Table 5.
Stability (% difference, n=3) of fortified meconium specimens and extracted specimens on the autosampler
| Analyte | 12 h room temperature
|
72 h 4 °C
|
3 freeze/thaw cycles
|
72 h autosampler (4 °C)
|
||||
|---|---|---|---|---|---|---|---|---|
| Lowa | Highb | Low | High | Low | High | Low | High | |
| Ethyl laurate | 15.0 | −7.5 | 9.0 | 10.3 | 9.3 | 16.3 | −1.6 | −7.7 |
| Ethyl myristate | 0.8 | 3.5 | −4.9 | −2.6 | 1.6 | −1.8 | −0.2 | 2.7 |
| Ethyl linolenate | 6.7 | 4.4 | −0.6 | 6.0 | −1.1 | 2.4 | 2.1 | 1.8 |
| Ethyl palmitoleate | −0.1 | −2.6 | 1.8 | 8.3 | 7.0 | 13.3 | 10.8 | 11.5 |
| Ethyl arachidonate | −0.2 | −1.4 | −9.3 | −8.3 | −2.3 | −5.3 | −7.4 | −5.0 |
| Ethyl linoleate | 0.8 | 3.7 | −0.6 | −0.6 | −0.9 | −1.1 | 3.4 | 8.5 |
| Ethyl palmitate | 7.7 | −1.0 | −5.7 | −3.7 | −1.4 | −5.2 | −8.3 | 4.6 |
| Ethyl oleate | −7.4 | −5.8 | −4.9 | −9.7 | −3.6 | −2.6 | −8.6 | −6.5 |
| Ethyl stearate | −3.7 | −2.0 | −1.3 | −6.6 | −3.7 | −1.5 | 7.0 | −6.2 |
| Ethyl sulfate (EtS) | −9.0 | 11.0 | −2.2 | 13.7 | 5.0 | 12.3 | −7.8 | 13.3 |
| Ethyl glucuronide (EtG) | 3.7 | 7.3 | 4.9 | 12.3 | −3.5 | 12.0 | −3.8 | 11.0 |
a
Low QC concentration was 150 ng/g for ethyl laurate, ethyl palmitate, and ethyl stearate; 75 ng/g for all other FAEE; 7.5 ng/g for EtS; and 15 ng/g for EtG
b
High QC concentration was 4,000 ng/g for all FAEE, except 2,500 ng/g for ethyl arachidonate, 450 ng/g for EtS, and 900 ng/g for EtG