Page 17 - Application Notebook - Solution for Food Safety

Application No.C136
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Table 1 LC and MS/MS Acquisition Parameters
Liquid chromatography Mass spectrometry
UHPLC Nexera LC system LC/MS/MS LCMS-8060
Restek Raptor Biphenyl Ionisation mode Heated electrospray
Analytical column
(2.1 mm I.D. × 100 mm L., 2.7 μm) Polarity switching time 5 msec
Column temperature 35 ˚C Pause time 1 msec
Flow rate 0.4 mL/min Total MRM transitions 1,919 (1,819 positive; 100 negative)
2 mmol/L ammonium formate 4 msec (target ion);
Solvent A MRM Dwell
+ 0.002 % formic acid - Water 1 msec (reference ion)
2 mmol/L ammonium formate Interface temperature 350 ˚C
Solvent B
+ 0.002 % formic acid - Methanol Heating block 300 ˚C
3 % (0 min) - 10 % (1.00 min) - Desolvation line 150 ˚C
Binary Gradient 55 % (3.00 min) - 100 % (10.50 - Heating gas 10 L/min
B.Conc.
12.00 min) - 3 % (12.01 - 15.00 min) Drying gas 10 L/min
Injection volume 2 μL sample (plus 40 μL water) Nebulizer gas 3 L/min

2.00 ×10 6

1.75

1.50

1.25

1.00

0.75

0.50

0.25

0
0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10.0 min
Fig. 1 MRM chromatograms of 646 pesticides spiked into a mint extract at 0.01 mg/kg
(Up to 3 MRMs per compound and 5 msec polarity switching time).

Carbendazim Pyraclostrobin
192.10 > 160.15 (+) 388.00 > 163.10 (+)
×10 6 CE: -6.0 CE: -14.0
1.2 Tebuconazole
308.20 > 70.05 (+) Chlorpyrifos
1.1 CE: -22.0 Cyprodinil 350.00 > 197.95 (+)
Boscalid 226.10 > 93 > 00 (+) CE: -21.0
1.0 343.00 > 306.95 (+) CE: -37.0
Propamocarb CE: -11.0
0.9 189.20 > 102.15 (+) Fenhexamid
CE: -8.0 302.10 > 70.05 (+)
0.8 CE: -22.0
Methomyl
0.7 163.00 > 87.90 (+)
CE: -10.0
0.6 Endosulfan
Thiacloprid -sulfate
0.5 252.80 > 126.05 (+) 420.80 > 97.00 (-)
CE: 35.0
CE: -11.0
0.4 Imidacloprid
256.10 > 174.95 (+)
CE: -20.0
0.3 Fludioxonil
247.00 > 180.15 (-)
0.2 CE: 28.0
0.1
0.0
0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10.0 11.0 min
Fig. 2 MRM chromatograms for pesticides most commonly detected in plant products listed in the 2015 European Food Safety
Journal. In this report, residues exceeding the legal limits were related to 58 different pesticides. Compounds such as boscalid,
chlorpyriphos, cyprodinil, fenhexamid, fludioxonil, pyraclostrobin and tebuconazole (highlighted in the MRM chromatogram)
are some of the most frequently detected compounds present in more than 4 % of the samples analyzed.
The MRM chromatograms show the response to each pesticide spiked into a food matrix at the default MRL of 0.01 mg/kg.