7000A GC-QQQ ApplicationsPesticides in Foods (3)

This application demonstrates

• Lack of cross-talk in the Agilent 7000A Triple Quad GC/MS

• Benefits of a GC/QQQ in MRM mode over a GC single Quad MS in SIM mode

• Ability of Agilent 7000A to achieve excellent sensitivity for pesticides in a difficult matrix such as ginger.

Cross Talk Test

• The following test has been designed to demonstrate the lack of cross talk in the Agilent 7000A Triple Quad GC/MS system.

• Cross talk or ion ghosting can be a source of error in quantitation. It is the result of a precursor ion entering the collision cell when product ions from the previous reaction monitord are still present.

• Inject on column a very high concentration of 3 pesticides (1 ng), chlorpyrifos, parathion and cyanazin. These pesticides co-elute under our multi-residue method at 13.5 minutes.

• The following ion traces show no cross talk even at these very high concentrations injected!

1.0 ng Chlorpyrifos on column5x10

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

1.8

2

2.2

2.4

2.6

2.8

3

3.2

3.4

3.6

3.8

4

4.2

4.4

4.6

4.8

5

5.2

5.4

5.6

5.8

6

6.2

6.4

+ MRM (314.00000 -> 189.00000) Cao_Mix_1_MRM_Cross Talk Test_29Aug.D

1 1 2 2

Counts vs. Acquisition Time (min)13.25 13.3 13.35 13.4 13.45 13.5 13.55 13.6 13.65 13.7 13.75 13.8 13.85 13.9

314→258

314→286

314→189

314→109

314→225

314→81

Chlorpyrifos

1.0 ng Parathion on column5x10

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

1.8

2

2.2

2.4

2.6

2.8

3

3.2

3.4

3.6

3.8

4

4.2

4.4

4.6

4.8+ MRM (291.00000 -> 81.00000) Cao_Mix_1_MRM_Cross Talk Test_29Aug.D

1 1 2 2

Counts vs. Acquisition Time (min)13.25 13.3 13.35 13.4 13.45 13.5 13.55 13.6 13.65 13.7 13.75 13.8 13.85 13.9

291→109

291→81

291→189

291→286

225→189

225→225

Parathion

1.0 ng Cyanazin on column5x10

0

0.05

0.1

0.15

0.2

0.25

0.3

0.35

0.4

0.45

0.5

0.55

0.6

0.65

0.7

0.75

0.8

0.85

0.9

0.95

1

1.05

1.1

1.15

1.2

1.25

1.3

1.35

1.4

+ MRM (225.00000 -> 189.00000) Cao_Mix_1_MRM_Cross Talk Test_29Aug.D

1 1 2 2

Counts vs. Acquisition Time (min)13.32 13.34 13.36 13.38 13.4 13.42 13.44 13.46 13.48 13.5 13.52 13.54 13.56 13.58 13.6 13.62 13.64 13.66 13.68 13.7 13.72 13.74

225→189

240→225

225→258

225→286

225→109

225→81

Cyanazin

GC-QQQ MRM vs Single Quad SIMDetamethrin in Garlic

3x10

0

0.05

0.1

0.15

0.2

0.25

0.3

0.35

0.4

0.45

0.5

0.55

0.6

0.65

0.7

0.75

0.8

0.85

0.9

0.95

1

1.05

1.1

1.15

+ MRM (253 -> 93) Cao_Garlic_5ppb_MRM_28Aug_Protectant.D

1 1 2 2 3 3 4 4 5 5 6 6 7 7 8 8 9 9

Counts vs. Acquisition Time (min)21.1 21.2 21.3 21.4 21.5 21.6 21.7 21.8 21.9 22 22.1 22.2 22.3 22.4 22.5 22.6 22.7 22.8 22.9

5.0ppb Deltamethrin

30ppb Deltamethrin

SIM results on a Single Quad MS GC-QQQ Results

It clearly demonstrates that GC-QQQ has much higher sensitivity in MRM mode than a single quadrupole in Selected Ion Monitoring (SIM) mode

GC-QQQ MRM vs Single Quad SIMOmethoate in Garlic

3x10

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

1.8

2

2.2

2.4

2.6

2.8

3

3.2

3.4

3.6

3.8

4

4.2

4.4

4.6

4.8

5

+ MRM (156 -> 79) Cao_Garlic_5ppb_MRM_28Aug_Protectant.D

1 1 2 2 3 3 4 4 5 5 6 6 7 7 8 8 9 9

Counts vs. Acquisition Time (min)9.2 9.25 9.3 9.35 9.4 9.45 9.5 9.55 9.6 9.65 9.7 9.75 9.8 9.85 9.9 9.95

10 ppb Omethoate. With excellent S/N at this low level it is easy to confirm presence confirm.

40 ppb Omethoate (R.T 9.705min) It looks good, but we can’t confirm it because the ion ratios are distorted seriously

GC-QQQ removes matrix interference and give more reliable confirmation

Garlic MRM TIC (Black) vs Ginger MRM TIC (Red)

Ginger Matrix is more complex than Garlic

5x10

-0.8

-0.6

-0.4

-0.2

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

1.8

2

2.2

2.4

2.6

2.8

3

3.2

+ TIC MRM (** -> **) Cao_Garlic_2_MRM_30Aug_Repro_02.D

Counts vs. Acquisition Time (min)5 5.5 6 6.5 7 7.5 8 8.5 9 9.5 10 10.5 11 11.5 12 12.5 13

Garlic MRM vs Ginger MRM

3x10

-0.2

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

1.8

2

2.2

+ MRM (156 -> 110) Cao_Ginger_2_MRM_30Aug_Repro_02.D

Counts vs. Acquisition Time (min)9.2 9.25 9.3 9.35 9.4 9.45 9.5 9.55 9.6 9.65 9.7 9.75 9.8 9.85 9.9 9.95 10 10.05 10.1 10.15 10.2 10.25

Although ginger is a very difficult matrix, GC-QQQ successfully eliminate the matrix interference, and omethoate has better S/N value (RMS=64) in ginger than in garlic (RMS=20)

5.0ppb Omethoate MRM results in Garlic (black and green) and Ginger (red and blue)

Garlic MRM TIC (Black) vs Ginger MRM TIC (Red)

5x10

-0.4

-0.3

-0.2

-0.1

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

1.1

1.2

1.3

1.4

1.5

+ TIC MRM (** -> **) Cao_Garlic_2_MRM_30Aug_Repro_02.D

Counts vs. Acquisition Time (min)15 15.2 15.4 15.6 15.8 16 16.2 16.4 16.6 16.8 17 17.2 17.4 17.6 17.8 18 18.2 18.4 18.6 18.8 19 19.2 19.4 19.6 19.8 20 20.2 20.4 20.6 20.8 21

Let’s look at another time segment

Garlic MRM v.s Ginger MRM

3x10

00.2

0.4

0.60.8

1

1.21.4

1.6

1.82

2.2

2.42.6

2.8

33.2

3.4

3.63.8

4

+ MRM (341 -> 183) Cao_Garlic_2_MRM_30Aug_Repro_02.D

Counts vs. Acquisition Time (min)17.52 17.54 17.56 17.58 17.6 17.62 17.64 17.66 17.68 17.7 17.72 17.74 17.76 17.78 17.8

5.0ppb Bromopropylate MRM results in Garlic (blue and red) and Ginger (green and brown)

Although MRM TICs are much different, the baselines are almost identical for Bromopropylate in ginger and garlic, S/N is 733 (RMS, ginger) and 283 (RMS, garlic) respectively.