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© 2015 AOAC INTERNATIONAL
(
10
)
Ion spray voltage
.—4000 V.
(
11
)
Dry gas temperature
.—350°C.
(
12
)
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(
13
) Monitored ion transitions, collision energies, and
fragmentation energies for the 20 pesticides and chlorpyrifos methyl
are shown in Table
2014.09F
, and SRM acquisition parameters by
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are shown in Table
2014.09G
.
(d)
Homogenizer
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(e)
Rotary evaporator
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equivalent.
(f)
Centrifuge
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Nitrogen
evaporator
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See
Figure
2014.09
.
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Variable volume pipets
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(k)
Balance
.—Capable of accurately measuring weights from
0.05 to 100 g within ±0.01 g.
F. Extraction and Cleanup Procedure
(a)
Sample extraction.—
(
1
) Weigh 5 g dry tea powder (accurate
to 0.01 g) into an 80 mL centrifuge tube.
(
2
) Add 15 mL acetonitrile.
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USP IRU PLQ
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4
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g
for 5 min at room temperature.
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evaporator (or TurboVap) in a 40°C water bath.
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(
9
) Mount a Cleanert TPT cartridge onto the manifold.
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10
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cartridge.
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the cartridge barrel has just reached the top of the sodium sulfate
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(b)
SPE cleanup
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F
(
a
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7
) into the conditioned Cleanert TPT cartridge collecting
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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
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Step
Time, min
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Mobile phase A
(0.1% formic acid in 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