Emerging Interest in GC-Triple Quadrupole Mass Spectrometry for Environmental Analysis National Environmental Monitoring Conference August 18, 2011 Jason Cole, Product Manager GC/MS
Presentation Overview • What are the analytical strengths of GC/QqQ? • Example applications demonstrating strengths • Organotins in water • Organotins in water • PAH in rubber • Dioxins in food and feed 2
Analytical Strengths of GC Triple Quadrupole
Triple Quadrupole MS – Principle of Operation Quantitation of target compounds in matrix samples Select Fragment Detect rce or Detecto Ion Sour Argon Collision Gas Q1 selects the precursor ion Q3 selects the product ion TCDD ion: m/z 319 90 TCDD ion: m/z 319.90 fragments to m/z 256 90 fragments to m/z 256.90 4
Analytical Strengths of Triple Quadrupole in SRM Analytical Strength Analytical Reason Application Benefit High sensitivity g y SRM has a high duty cycle g y y Lowered LOQ’s/LOD’s High selectivity Hi h l ti it MS/MS MS/MS eliminates most li i t t L Lowered LOQ’s/LOD’s d LOQ’ /LOD’ isobaric interferants Less sample prep Hi h High speed of analysis d f l i High specificity MS/MS eliminates most Less false positives isobaric interferants SRM process offers opportunity for lowered LOQs, reduced sample prep, higher speed of analysis and less risk of false positives speed of analysis, and less risk of false positives 5
Organotins in Drinking Water Organotins in Drinking Water
Application Challenge and Approach • Lowered limits set by EU Water Directive • Maximum allowable concentration – 1.5 ng/L (ppt) • Maximum annual average – 0.2 ng/L (ppt) • Approach • Extraction • 400 ml of water at pH5 • Extraction with pentane • Evaporated to 400 µl E t d t 400 l • Derivatized with sodium tetra-ethyl borate • 3 µL injected into TSQ Quantum XLS GC triple quadrupole • 3 µL injected into TSQ Quantum XLS, GC triple quadrupole 7
Customer Limits of Detection Using SIM Compound LOD Using SIM Monobutyltin 10 ng/L Dibutyltin 5 ng/L Tributyltin 5 ng/L Triphenyltin Triphenyltin 1 ng/L 1 ng/L Greater than order of magnitude improvement in detection limits needed detection limits needed 8
Organotins at 0.5 ng/L Injection of 0.2 pg absolute on column Corresponding with 0.05ng/L in water sample New EU directive: 0.2ng/L for tributyltin and here 0.05ng/l is shown 9
PAHs in Rubber PAHs in Rubber
The Case of the Problem Sample • Sample matrix: rubber • Looking for PAH’s that come from extender oils • Full sample prep applied to sample 11
Comparison of Fullscan and SRM Pyrene in rubber by fullscan Pyrene in rubber Pyrene in rubber by SRM Pyrene in Standard Pyrene in Standard by SRM 12
Compounds Detected – SRM vs Fullscan Compound SRM* Fullscan Naphthalene Naphthalene X X X X Acenaphthylene X Acenaphthene X Anthracene Anthracene X X Phenanthrene X Pyrene X * All compounds confirmed with retention times and ion ratios (2) p ( ) 13
Benefits of Triple Quad for the Analysis • Less sample prep required • Ability to measure “worst case” samples Ability to measure worst case samples • Greater confidence in confirmation 14
Dioxins in Food and Feed Dioxins in Food and Feed
Why GC-Triple Quad for Dioxins Analysis? • Screening • Higher quality of screening results • TEQs can be calculated from results of screen [1] • Congener specific - Results depend on PCDD/F and PCB congener profile • Improvement of screening sensitivity for false negative results below 1% Impro ement of screening sensiti it for false negati e res lts belo 1% • Could result in a improved specificity, thus affecting the overall cost. [2] • Confirmation C fi ti • Lower upfront cost • More versitile approach • References: • [1] Kotz, Malisch 2010, Dioxon Conference • • [2] Fochi Brambilla 2008 [2] Fochi, Brambilla 2008 16
Maximum Allowed Levels Commission Regulation (EC) No. 1881/2006 Commission Directive 2006/13/EC) Commission Directive 2006/13/EC) 17
TSQ Quantum XLS TSQ Quantum XLS - TCDD in Buffalo Milk Samples Blank Blank (GC (GC- -MS/MS) MS/MS) Buffalo Milk (GC Buffalo Milk (GC- -MS/MS) MS/MS) Buffalo Milk (GC- Buffalo Milk (GC -HRMS) HRMS) 0.17 pg/g fat TCDD 2,3,7,8-T TCDD - 2,3,7,8 STD Labeled IS 18
Buffalo Milk Sample, HxCDD GC-MS/MS (5 µl injection PTV solv. split ) GC-HRMS 1/10 concentration GC MS/MS GC-MS/MS GC HRMS GC-HRMS RT: 30.33 - 32.83 SM: 5G RT: 25.25 - 27.74 SM: 5G RT: 26.44 NL: NL: 1.69E4 RT: 31.50 4.85E2 AA: 2188 AA: 82403 TIC F: + c EI SRM 100 m/z= 100 ms2 389.816 389.7160- [326.802-326.902] MS 80 80 389.9160 MS ICIS 100819_25956 RT: 26.71 BuffaloMilkA_Diox 60 60 A_16 RT: 26.32 MA: 783 AA: 839 AA: 839 40 40 RT: 31.31 RT: 31.99 AA: 14899 AA: 18515 20 20 25.46 25.57 26.09 27.00 27.32 25.90 27.62 0 NL: 9.42E3 NL: RT: 31.51 RT: 26.43 4.19E2 AA: 1638 AA: 53857 TIC F: + c EI SRM 100 100 m/z= ms2 391.813 ndance dance 391.7130- [328.799-328.899] MS 80 80 391.9130 MS ICIS RT: 26.70 RT: 26.70 ICIS ICIS Relative Abun Relative Abun BuffaloMilkA_Diox RT: 26.32 60 60 AA: 631 100819_25956 AA: 628 A_16 RT: 31.98 40 40 RT: 31.33 AA: 11221 AA: 5188 20 20 0 NL: 2.57E6 RT: 31.97 NL: RT: 26.69 6.00E4 AA: 13708676 TIC F: + c EI SRM AA: 304546 100 100 m/z= ms2 401.856 401.7560 401 7560- [337 839 337 939] MS [337.839-337.939] MS 80 80 401.9560 MS ICIS ICIS BuffaloMilkA_Diox 60 60 100819_25956 A_16 RT: 31.48 RT: 26.43 40 40 AA: 76282 AA: 3508171 20 RT: 32.26 20 AA: 49104 0 NL: 1.65E6 RT: 31.97 NL: RT: 26.69 4.88E4 TIC F: c EI SRM TIC F: + c EI SRM AA: 8797425 AA: 8797425 AA: 242407 AA: 242407 100 100 ms2 403.853 m/z= 403.7530- [339.836-339.936] MS 80 80 403.9530 MS ICIS ICIS BuffaloMilkA_Diox 60 60 100819_25956 A_16 RT: 31.49 RT: 26.43 40 40 AA: 2309415 AA: 59305 20 RT: 32.26 20 RT: 26.96 AA: 33481 AA: 2074 0 0 30.5 31.0 31.5 32.0 32.5 25.5 26.0 26.5 27.0 27.5 Time (min) Time (min) 19
TSQ Quantum XLS vs. GC-HRMS of Certified Material TSQ Quantum XLS 2.00 TSQ HRMS CERTIFIED LOQs 1.80 1 80 1.60 Results in [pg TEQ/g fat] 1.40 TSQ 3,22 (5% RSD) HRMS 3 23 (2% RSD) HRMS 3.23 (2% RSD) 1.20 1.00 0.80 0.60 0.40 0.20 0 20 0.00 D D D D D D D F F F F F F F F F F D D D D D D D D D D D D D D D D D C C C C C C C C C C C C C C C C C T e e x x x x p p O x x x p T e O P P H H H H H H P H H H H - - 8 - - 8 - - - - - - - - - 8 8 8 - - , 8 8 9 8 8 9 , 8 8 9 8 7 , , 7 , 7 7 , , , , , , , , , , 7 7 8 7 , 7 , 7 8 7 3 7 8 7 , , 3 3 4 , , , , , , , , , , , 3 , , 2 4 6 7 6 6 7 4 4 6 7 6 , , 2 2 2 2 3 3 , , , , , , , , , , , , , , , , 2 2 , , , , , , 3 3 3 3 3 3 4 4 4 4 4 4 3 3 3 3 3 3 4 4 , , 1 1 2 2 , , , , , , , 1 , , , , 2 2 2 3 3 3 2 2 2 3 , , , , , , , , , , 1 1 1 2 2 2 1 1 1 2 , , , 1 1 1 Courtesy N. Iacovella, G. Brambilla, ISS, Rome, Italy 20
TSQ Quantum XLS Ultra – Food Dioxin Screening • Courtesy Alexander Kotz, EURL Freiburg, Germany • Presented at the 6th POPs Users Meeting, Niagara-on-the-Lake, Canada, Apr 28/29, 2011 100 Deviation of MS/MS Deviation of MS/MS Food Samples from HRMS 80 [%] of HRMS 60 40 MS/MS results o 20 0 0 1 2 3 4 5 6 7 8 9 10 Deviation of M -20 20 -40 -60 Measurement of same extracts Measurement of same extracts -80 using DFS GC-HRMS and TSQ Butter, Eggs, Meat and Fat EU Maximum Levels -100 Quantum XLS Ultra GC-MS/MS WHO-PCDD/F-TEQ [pg/g fat] Butter Eggs Fat Meat Human milk 21
Conclusion From Webinar by Dr. Kotz • GC-MS/MS systems in principle applicable for PCDD/F and DL-PCB analysis in food and feed samples • Sensitive enough to check for dioxins at maximum allowed levels • GC/HRMS still preferred at lower concentration 22
Presenation Summary • Laboratories are showing increasing interest in GC triple quad technology because of inherent advantages in the technology: • Low LOQ’s from combination of high selectivity with high sensitivity Q g y g y • High specificity for more confident results • Examples of application of technology • Examples of application of technology • Organotins in drinking water for reduced LOQ’s • PAH in rubber for confident detection in worst case matrix scenario • Dioxins in food and feed for higher sensitivity/specificity screening 23
Thank you very much for Thank you very much for your attention! 24
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