342 / 471
Table 2014.09C. GC-MS/MS retention times, monitored ion transitions, collision energies, LODs, and LOQs for the 20 pesticides
No.
Pesticide
Retention
time, min
Quantifying precursor/
product ion transition
Qualifying precursor/
product ion transition Collision energy, V
LOQ, μg/kg
LOD, μg/kg
ISTD
Heptachlor-
epoxide
22.15
353/263
353/282
17;17
1
Trifluralin
15.41
306/264
306/206
12;15
4.8
2.4
2
Tefluthrin
17.40
177/127
177/101
13;25
0.8
0.4
3
Pyrimethanil
17.42
200/199
183/102
10;30
6.0
3.0
4
Propyzamide
18.91
173/145
173/109
15;25
1.0
0.5
5
Pirimicarb
19.02
238/166
238/96
15;25
4.0
2.0
6
Dimethenamid
19.73
230/154
230/111
8;25
2.0
1.0
7
Fenchlorphos
19.83
287/272
287/242
15;25
16.0
8.0
8
Tolclofos-methyl
19.87
267/252
267/93
15;25
10.0
5.0
9
Pirimiphos-methyl
20.36
290/233
290/125
5;15
10.0
5.0
10
2,4'-DDE
22.79
318/248
318/246
15;15
6.0
3.0
11
Bromophos-ethyl
23.16
359/303
359/331
10;10
10.0
5.0
12
4,4'-DDE
23.90
318/248
318/246
25;25
4.0
2.0
13
Procymidone
24.70
283/96
283/255
10:10
2.0
1.0
14
Picoxystrobin
24.75
335/173
335/303
10;10
10.0
5.0
15
Quinoxyfen
27.18
237/208
237/182
25;25
80.0
40.0
16
Chlorfenapyr
27.37
408/59
408/363
15;5
140.0
70.0
17
Benalaxyl
27.66
148/105
148/79
15;25
2.0
1.0
18
Bifenthrin
28.63
181/166
181/165
10;5
10.0
5.0
19
Diflufenican
28.73
266/218
266/246
25;10
20.0
10.0
20
Bromopropylate
29.46
341/185
341/183
15;15
8.0
4.0
Table 2014.09D. SRM acquisition parameters by GC-MS/MS analysis for the 20 pesticides of interest
Group Start time, min
Monitored ion transitions,
m/z
Dwell time, ms
1
14.76
306/264,306/206
50
2
15.87
177/127,177/101,200/199,183/102
50
3
18.06
173/145,173/109,238/166,238/96
50
4
19.26
230/154,230/111,287/272,287/242,267/252,267/93
25
5
20.07
290/233,290/125
50
6
21.87
353/282,353/263
50
7
22.60
359/331,359/303,318/248,318/246
50
8
23.59
335/303,335/173,318/248,318/246,283/96,283/255
50
9
26.71
148/105,148/79,408/363,408/59, 237/208, 237/182
25
10
27.88
266/246,266/218,181/166,181/165
50
11
28.96
341/185,341/183
50
Table 2014.09E. Gradient conditions for LC-MS/MS analysis
Step Time, min
Flow rate, μL/min
Mobile phase A
(0.1% formic acid water), %
Mobile phase B
(acetonitrile), %
0
0.00
400
99.0
1.0
1
3.00
400
70.0
30.0
2
6.00
400
60.0
40.0
3
9.00
400
60.0
40.0
4
15.00
400
40.0
60.0
5
19.00
400
1.0
99.0
6
23.00
400
1.0
99.0
7
23.01
400
99.0
1.0
Candidates for 2016 Method of the Year
282