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Advantages of a tandem MS as a Chromatographic Detector ‐Multiple Reaction Monitoring (MRM)
170 210 250 290
210
222
268 280165
Spectrum with
backgroundions (from EI)
Q1 lets only target ion 210 pass through
190 210
210
Collision cell breaks ion 210 apart
150 170 190 210
210158
191
Q2 monitors fragments 158
and 191 for quant and qual.
160
158
190
191
no chemical background
Quad Mass Filter (Q2)Quad Mass Filter (Q1) Collision CellSource
MS/MS Eliminates Scan and SIM Interferences
analyte
Product 1Product 3
Product 2
Single Quad MSno selectivity against ions
with same m/z
Tandem MSSelectivity by selection of product ions
interference
analyte
interference
unit mass resolution
MS/MS Ensures Lowest Detection LimitsEI: spectrum of analyte can also include
ions from matrix, column bleed, gases, etc.
Q1 SIM isolate precursor before CID
Product 1Product 3
Product 2
CID +Q2 SIM
Lower m/z Product Ions measured against “zero” chemical noise
chemical noise from other ions
eliminated
Seven Injections of Pesticide Mix at 1.67 ppbExcellent RT reproducibility with GC/MSMS MRM
4x10
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
1.6
1.7
1.8
1.9
2
2.1
+EI TIC MRM (** -> **) pest_1_67ppb_1x_1.D
Counts vs. Acquisition Time (min)6.2 6.3 6.4 6.5 6.6 6.7 6.8 6.9 7 7.1 7.2 7.3 7.4 7.5 7.6 7.7 7.8 7.9 8 8.1 8.2 8.3 8.4 8.5 8.6 8.7 8.8 8.9 9
Carrot Extract with Known Pesticide Residues
A Food Chemist submitted a carrot extract sample that they had analyzed in their lab and said we would find:
Chlorpyrifos
DDT
Could we use the Agilent GC/MSMS to find and quantify these compounds?
Carrot Extract with “known” Pesticide Residues
The Food Chemist said we would find:
Chlorpyrifos
DDT
Using the Agilent 7000A GC/MSMS, we also found
Chlorpyrifos
Etridiazole Tolylfluanid
Trifluralin DDE (DDT breakdown product)
Heptachlor Iprodione
Gamma‐Chlordene Mirex
Dioxins and FuransPreliminary investigation of polychlorinated dioxins and
furans on the Agilent 7000A GC‐QQQ
With thanks to Anthony Macherone
Samples Submitted
CS‐1: evaporated 2,3,7,8‐tetrachlorodibenzo‐p‐dioxin(TCDD) & 2,3,7,8‐Tetrachlorodibenzo‐p‐Furan (TCDF) mix, reconstituted in 50 μl toluene to create 250 fg / μl solution
CS‐1: evaporated TCDD & TCDF mix, reconstituted in 50 μl toluene to create 1000 fg / μl solution
TCDD & TCDF Method
Column: HP-5MS UI 30m, 0.25mm-id, 0.25 filmCarrier: He - 1.0 ml/min constant flowOven Table: Ramp oC / min Tf
oC Hold (min)0 100 0.4
100 200 67.5 235 420 310 3
Inject: 1 μl, pulsed splitless: 25 ml / min for 0.5 minInject T: 300 oCAux 2: 310 oCSource T: 300 oCeV: 70Q1 = Q2: 150 oC
MRM Table
Compound Window Transition Fragment 1 Ion type Ion Ratio ParentTCDF 1 306 > 241 -65 M/M+2 < 1 M+2TCDD 1 322 > 257 -65 M/M+2 < 1 M+2
P5CDF 2 340 > 277 -63 M+2/M+4 > 1 M+2P5CDD 2 356 > 293 -63 M+2/M+4 > 1 M+2
H6CDF 3 374 > 311 -63 M+2/M+4 > 1 M+2H6CDD 3 390 > 327 -63 M+2/M+4 > 1 M+2
H7CDD* 4 426 > 361 -65 M+2/M+4 ~ 1 M+4
H7CDF* 5 410 > 345 -65 M+2/M+4 ~ 1 M+4OCDF* 5 444 > 379 -65 M+2/M+4 < 1 M+4OCDD 5 460 > 395 -65 M+2/M+4 < 1 M+4
*Predicted values based on table trends
Pentachloro‐dibenzodioxin (P5CDD) and pentachloro‐dibenzofuran (P5CDF) 500 fg/µl each
2x10
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
+ MRM (356.0 -> 293.0) CS-1_102908_MRM_1ul.D Smooth (1) Noise (RMS) = 0.56; SNR (17.241min) = 152.0
* 27117.241
3 3
2x10
0.4
0.5
0.6
0.7
0.8
0.9
1
1.1
1.2
1.3
1.4
1.5
1.6
1.7
+ MRM (340.0 -> 277.0) CS-1_102908_MRM_1ul.D Smooth (1) Noise (RMS) = 0.22; SNR (16.296min) = 649.7
* 57716.296
32816.960
3 3
Counts vs. Acquisition Time (min)16.1 16.2 16.3 16.4 16.5 16.6 16.7 16.8 16.9 17 17.1 17.2 17.3 17.4 17.5 17.6 17.7 17.8 17.9 18 18.1 18.2 18.3 18.4
P5CDF – 2 isomers
P5CDD
Representative MRM’s for 1000 fg & 250 fg on column
October 30, 200823
2x10
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
+ MRM (340.0 -> 277.0) CS-2_102908_MRM_1ul.D Smooth (1)
16.32252
17.01348
2 3
Counts vs. Acquisition Time (min)15.7 15.8 15.9 16 16.1 16.2 16.3 16.4 16.5 16.6 16.7 16.8 16.9 17 17.1 17.2 17.3 17.4 17.5 17.6 17.7 17.8 17.9 18 18.1
P5CDF – 2 isomers
P5CDD
Hexachloro‐dibenzodioxin (H6CDD) and Hexachloro‐dibenzofuran (H6CDF) 500 fg/µl each
2x10
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
+ MRM (390.0 -> 327.0) CS-1_102908_MRM_1ul.D Smooth (1) Noise (RMS) = 0.28; SNR (19.282min) = 311.8
311.819.282
* 258.219.105
* 156.419.148
4
2x10
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
+ MRM (374.0 -> 311.0) CS-1_102908_MRM_1ul.D Smooth (1) Noise (RMS) = 0.28; SNR (18.762min) = 271.0
* 271.018.762
254.919.038* 246.1
18.711
221.619.362
4
Counts vs. Acquisition Time (min)18.55 18.6 18.65 18.7 18.75 18.8 18.85 18.9 18.95 19 19.05 19.1 19.15 19.2 19.25 19.3 19.35 19.4 19.45 19.5 19.55 19.6 19.65
H6CDD, 3 isomers
H6CDF, 4 isomers
Heptachloro‐dibenzodioxin (H7CDD) 500 fg/µl
2x10
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
1.45
1.5
1.55
1.6
1.65
1.7
+ MRM (426.0 -> 361.0) CS-1_102908_MRM_1ul.D Smooth (1) Noise (RMS) = 0.29; SNR (20.037min) = 473.0
473.020.037
Counts vs. Acquisition Time (min)19.76 19.78 19.8 19.82 19.84 19.86 19.88 19.9 19.92 19.94 19.96 19.98 20 20.02 20.04 20.06 20.08 20.1 20.12 20.14 20.16 20.18 20.2 20.22 20.24 20.26 20.28 20.3 20.32 20.34 20.36 20.38
H7CDD
Octochloro‐dibenzodioxin (OCDD), Octochloro‐dibenzofuran (OCDF) and Hexachloro‐dibenzofuran (H7CDF)
OCDD (1000fg/ul)
OCDF (1000fg/ul)
H7CDF (500fg/ul),
co-elution of 2 isomers
Compound list with retention times and S/N
Compound Window Transition Injection V (µl) Conc. (fg/µl) r.t. (min) S/NTCDD 1 322 > 257 1 250 13.038 169TCDF 1 306 > 241 1 250 13.045 112
P5CDF 2 340 > 277 1 500 16.296 650P5CDF 2 340 > 277 1 500 16.960 457P5CDD 2 356 > 293 1 500 17.241 152
H6CDF 3 374 > 311 1 500 18.711 246H6CDF 3 374 > 311 1 500 18.762 271H6CDF 3 374 > 311 1 500 19.038 245H6CDF 3 374 > 311 1 500 19.362 222H6CDD 3 390 > 327 1 500 19.105 258H6CDD 3 390 > 327 1 500 19.148 156H6CDD 3 390 > 327 1 500 19.282 312
H7CDD 4 426 > 361 1 500 20.037 473
H7CDF 5 410 > 345 1 500 21.809 1478H7CDF 5 410 > 345 1 500 21.809 1478OCDF 5 444 > 379 1 1000 21.865 45OCDD 5 460 > 395 1 1000 21.812 119
Observations and further work
Method needs more optimisation.
• Isomeric forms will be quantified using appropriate standards
Selected limited set of transitions in this preliminary study
• But was still able to predict MRM trends based on the available library data
Able to reduce run time from 55 min to 23 min using method translator
• 60m DB‐5 column to 30m HP‐5MS UI column
Observed very low chemical noise in the TCDD / TCDF set
DL of 250 fg/μl achieved
• With additional optimization may be able to improve to a LOD of ~ 25 fg/μl – For select compounds based on lowest S/N ratio.
Nitro‐Polycyclic Aromatic Hydrocarbons in Air
ParticulatesInvestigation of nitro‐polycyclic hydrocarbons in air utilizing the Agilent 7000A GC‐QQQ
Thanks to:Frank DavidRIC, Belgium
30
Determination on Nitro‐Polycyclic Aromatic Hydrocarbons in Air Particulates
Air particulates are sampled on glass fiber filter (1000 m³ air) – Soxhlet extraction – concentration of extract (1 mL)
Direct analysis by GC‐MS (SIM MODE) not possible due to too high/complex matrix
Clean‐up by HPLC (normal phase) followed by GC‐MS analysis (SIM mode)
Alternative: two‐dimensional GC with MS (SIM)
24 u @ 1,13 m3/min
glass fiber filter
Current Methodology
Determination on Nitro‐Polycyclic Aromatic Hydrocarbons in Air ParticulatesExtract: 1000 m³ in 1 mL (toluene)
15 m x 0.25 m x 0.25 µm DB‐5MSUI column
1 µL splitless injection
Fast ramp (70°C – 1 min – 20°C/min – 310°C)
• GC chromatogram even more “compressed” than classical method
MRM from molecular ion to M‐46 (‐NO2) and/or M‐30 (‐NO)
• Nitro‐naphthalene: 173 → 127• Nitro‐anthracene: 223 → 193• Nitro‐fluoranthene: 247 → 201• Nitro‐pyrene: 247 → 201
• Concentration NO2‐PAHs 100‐1000 X lower than PAHs (typical concentration in urban air particulates: 10‐100 pg/m³)
Nitro PAHs in air particulatesGC/QQQ – MRM – 50 pg/mL Calibration Standard)
1-N
itro-
Nap
htha
lene
9-N
itro-
Ant
hrac
ene
3-N
itro-
Fluo
rant
hene
1-N
itro-
Pyr
ene
2-N
itro-
Pyr
ene
GC/QQQ – MRM – Sample (extract air particulates – without clean‐up)
Nitro-naphthalene
Nitro-anthracene
Nitro-fluoranthene Nitro-pyrene
GC‐MS‐MS – MRM – Sample (extract air particulates – without clean‐up)
Nitro-naphthalene Nitro-anthracene
GC/QQQ vs GC/MS (SIM)(extract air particulates – without clean‐up)
Nitr
o-flu
oran
then
e
Nitr
o-py
rene12.00 12.20 12.40 12.60 12.80 13.00 13.20 13.40 13.60 13.80
0
200
400
600
800
1000
1200
1400
1600
1800
2000
2200
Time-->
Abundance
Ion 247.00 (246.70 to 247.70): nitropah-12.D\DATASIM.MS
12.00 12.20 12.40 12.60 12.80 13.00 13.20 13.40 13.60 13.800
200
400
600
800
1000
1200
1400
1600
1800
2000
2200
Time-->
Abundance
Ion 201.00 (200.70 to 201.70): nitropah-12.D\DATASIM.MS
SIM (5975C)
?
MRM (G7000A)
Determination on Nitro‐Polycyclic Aromatic Hydrocarbons in Air Particulates
Detected concentrations:
• 1‐nitro‐naphthalene: 21 pg/m³
• 9‐nitro‐anthracene: 57 pg/m³
• 3‐nitro‐fluoranthene: 77 pg/m³
• 2‐nitro‐pyrene: 14 pg/m³
No clean‐up
Faster GC analysis
QQQ offers higher specificity – higher selectivity
Agilent 7000A GC/QQQ
Outstanding sensitivity 100 fg of OFN on column at 100:1 S/N RMS in MS/MS mode using AUTOTUNE parameters verified at customer installation
1050 amu Mass Range
500 MRM/sec Speed
Reliable heated monolithic gold plated hyperbolic quadrupoles
Differentially pumped vacuum system
New Helium seeded collision cell technology
Agilent 7890A GC with Capillary Flow Technology
MassHunter Software
April, 2009ESAC2009