Table 3.
Results from ID-LFIA/DART-QqQ-MS/MS analysis and the respective LFIA smartphone screening of AcDON-spiked wheat samples at three target levels and the analysis of an incurred corn starch sample.
| TL | ID-LFIA/DART-QqQ-MS/MS | LFIA Smartphone Screening Result (mg/kg, Mean Response ± SD) | ||||
|---|---|---|---|---|---|---|
| Mean Ion Area Ratio of DON ± SD | Response Factor ± SD | Mean Ion Area Ratio of AcDON ± SD |
Response Factor ± SD | |||
| AcDON-spiked wheat | 0.5 | - | - | 0.73 (±0.06) | 0.09 (±0.01) | 0.64 (±0.01) |
| 1 | - | - | 0.76 (±0.03) | 0.16 (±0.02) | 1.87 (±0.04) | |
| 1.5 | - | - | 0.65 (±0.02) | 0.31 (±0.01) | 2.62 (±0.03) | |
| Contaminated corn starch | 0.32 (±0.09) | 0.82 (±0.08) | 0.71 (±0.08) | 0.45 (±0.05) | 12.76 (±0.07) | |
Conditions: duplicate sampling of the same final ID-LFIA dissociation solution in DART-QqQ-MS/MS. SD is the standard deviation of the duplicate measurements. The screening result was performed with the r-Biopharm LFIA, and the quantification was done with the associated smartphone app. SD is the standard deviation of duplicate reading of the same LFIA. The response factor for DON is the mean area ratio of the MRM product ion at m/z 249.2 and the 13C15 DON ion at m/z 263.2, and for AcDON the ratio of the MRM product ion at m/z 231.1 and the 13C15 DON ion at m/z 263.2. The DON ion ratio is the ratio of the absolute area of the DON MRM product ion at m/z 231.1 to the area of the ion at m/z 249.2 and for AcDON the ratio of the MRM product ions at m/z 203.1 and m/z 231.1.