Scott Krepich Senior Field Application Scientist

Scott Krepich Senior Field Application Scientist
Modern Approaches for PFAS LC-MS/MS Analysis in Aqueous and Solid Matrices Scott Krepich Senior Field Application Scientist

Overview PFAS Background Case Studies Conclusion Resources
SPE + LC-MS/MS Large Volume Direct Inject + LC-MS/MS QuEChERS from Food + UHPLC-MS/MS Online SPE + LC-MS/MS QuEChERS from Sediment + LC-MS/MS Conclusion Resources Acknowledgements

EPA Guidelines for PFOA and PFOS In Drinking Water
PFAS PFAS – Per and Polyfluorinated Alkyl Substance Repellent properties popular for consumer products like surface treatment protection, paper protection, and performance chemicals (i.e. firefighting foams) Trace levels found throughout global water sources Chemically stable, low reactivity, and resistant to degradation in aqueous environments - Important for use in a wide range of products and industrial applications Human exposure to PFAS residues linked to adverse health effects Per and Polyfluorinated Alkyl substances or PFASs, are aliphatic substances with fluorine substitutions on one or more carbon atoms that have found extensive utility as surfactants, fire fighting foams, and commercial products like non-stick cooking pans. They are also very stable in aqueous environments, and are found throughout the global water supply. Some of the longer chained ones, such as P-F-O-A (perflurooctanoic acid) and P-F-O-S (perflourooctane sulfonic acid) can bioaccumulate in mammals and lead to many adverse health effects. As such, the EPA has established health advisory levels at 70 ppt to give a margin of protection from a lifetime of exposure, thus leading to an increased need for constant trace level testing in drinking water and water supply sources. EPA Guidelines for PFOA and PFOS In Drinking Water = More Testing

Typical Challenges Variety of Compounds Wide Range of
Chemical Properties Wide Range of Sample Matrices Acidic Basic From our familiar testing challenges that come from the range of compounds with a wide range of chemical properties and sample matrices … Neutral 4

PFAS Specific Challenges
System Contamination Trace Quantities Wide Hydrophobic Range Isobaric We have a subset of challenges to work through here, with potential PFAS interferences from the system components and solvents, the trace levels we’ll be looking for, the wide range of hydrophobicities present, as well as some branched structural isomers that are important to monitor. 5

Solid Phase Extraction
The Strata®-X Product Line Solid Phase Extraction In SPE, a support particle is modified with different functional groups Silica or polymeric particles Wide range of functional groups (RP, IEX, NP) Target analytes bind to the media Matrix interferences are washed away using different washing protocols The key distinction is that you optimize your method to target & recover your analytes More selective than QuEChERS Solid Phase Extraction, the most selective of the sample preparation techniques covered, is ideal when target analytes can be isolated by hydrophobicity or a specific functionality like ion-exchange. The sorbent is a solid support particle modified with functional groups designed to target and retain analytes of interest while washing away matrix interferences, before eluting analytes of interest for further analysis. Phenomenex’s brand of functionalized polymeric SPE sorbents is Strata-X, and is available in reversed phase and mixed-mode ion-exchange and in tube, well-plate and on-line formats. 6

Strata®-X-AW and XL-AW
Weak Anion-Exchange 3 Mechanisms of Retention All or most PFAS analyses are looking at acids, with a wide range of hydrophobicities. As such, an anion-exchange handle can help increase retention strength for improved clean-up and recovery. Strata X-AW is a mixed-mode, weak anion-exchanger, with a primary and secondary diamine ligand bound to a hydrophobic polystyrene divinylbenzene backbone. This will allow us to collect some of the less hydrophobic PFASs, like perfluorobutanoic acid (PFBA) with good recovery due to a stronger ionic interaction to the sorbent.

Large Volume Processing and Online SPE
When looking at trace quantities in water samples that are impractical to concentrate through evaporation, we can load a large sample volume onto a syringe barrel tube format with a simple adapter cap to apply samples manually through an empty barrel or connective tubing to a large volume reservoir appropriate for loading 100mL up to a liter or sometimes 4 liters.

EPA method 537 Reversed phase retention (Strata®-X) Mixed Mode Anion-Exchange Anion-Exchange + Strata-X Strata-X-A Strong Anion-Exchange Strata-X-AW Weak Anion-Exchange

Strata®-X-AW Weak Anion-Exchange Condition: 3 x 5mL methanol Condition: 2 x 5mL water Load: 125 mL sample Wash: 2 x 5 mL water Bottle rinse: 5 mL 0.5% NH4OH in methanol Elute: 3 x 5 mL 0.5% NH4OH in methanol Evaporate to dryness Reconstitute with 50/50 methanol/water

Gemini® TWIN™ Technology
Gemini columns are rugged reversed phase HPLC columns that offer extended lifetime at extreme pH conditions and excellent stability for reproducible, high efficiency separations. • Take full advantage of high and low pH conditions (pH 1-12) to manipulate selectivity • Expect longer column lifetime • For analytical and preparative separations of basic and acidic compounds In the first two case studies, we actually take advantage of the selectivity of one of our older HPLC column chemistries, Gemini C18, which is a high surface area, fully porous, hybrid silica particle with an organic polymer protection rationed towards the particle surface. This protects from degradation at the pH extremes, and happened to result in good selectivity in the PFAS application. PFBA retention and good peak shape

LUNA® Omega PS C18 LUNA Omega 1.6 & 5 µm Silica Based
3-step bonding process: Deposition of positive charge on surface C18 bonding TMS endcapping A C18 with: Enhanced selectivity for polar acids Stability in 100% aqueous mobile phases Improved peak shape and loadability for bases In the third case study, our state of the art Luna Omega particle technology with a PS C18 ligand was implemented in a UHPLC separation. The unique performance of the PS C18 phase is obtained by performing a three-step bonding process in which we first deposit a positive charge on the surface of the silica. This is then followed by conventional bonding with a C18 ligand, followed by TMS endcapping. The end result is a unique mixed-mode stationary phase that provides incredibly useful polar and non-polar retention properties.

Enhanced Selectivity for Acids
here is a great example of the unique selectivity of the Luna Omega PS C18 phase, in this case for the separation of two highly polar dicarboxylic acids, methyl malonic acid and succinic acid, that otherwise don’t retain well on traditional C18 phases. The positive surface charge of the Luna® Omega PS C18 provides the necessary increase in retention of these two acids through ionic and polar interactions, allowing for separation and quantification. Comparative separations may not be representative of all applications.

So Let’s Put These Into Action!
Considering the underlying contributing factors and bringing in a high powered Sciex mass spec into the workflow, we can integrate these into optimal solutions, suitable for industry and specific laboratory needs. Let’s go ahead and take a look at some of these PFAS solutions. Sample/Analyte Sample Preparation Column System Detector

PFAS using SPE and LC/MS/MS Case Study 1
Our first case study is using Solid Phase Extraction and HPLC-MSMS on a Sciex 5500 Triple Quad Presented by Scott

Reducing LC Contamination
Reducing background LC contamination is critical to obtaining low detection limits Important to use high-purity solvents and modifiers (e.g. ammonium acetate) for mobile phases; test each solvent bottle to verify purity PFAS may be present in plastic tubing, Teflon® filters Replace fluorinated tubing with PEEK Remove PFTE solvent filter frits Replace graphite-filled PTFE pump seals with polyethylene seals However, PFAS contamination may still be present … And while we want to take precautions to eliminate as much background interference as possible, with high purity solvents and removing fluorinated system components, there still may be some contamination that persists.

LC Contamination: Delay Column
The delay column is installed after the pump gradient mixer, and before the injector, so that during the gradient, system pfas will retain on the delay column, eluting with the gradient onto the column just after the sample injection. I recommend a high surface area, densely bonded C18 for the delay column, such as the Luna C18(2) that was used here, with the goal of overall retentivity equal to or greater than the analytical column. Here selectivity and efficiency are less important.

LC Contamination: Reduction Strategies
Use of “delay” or “trap” column placed between the pumps and autosampler, upstream of the analytical column PFAS leaching from the LC will be retained on the delay column and separated from the analytical peak NOT helpful for contamination from method blanks, contaminated standards And so the delay column concept that I mentioned in the introduction can be a very simple and practical way to prevent system related PFASs from interfering with the analysis. As the name implies, it delays system related components, slowing them down before sample or standard injection, and eluting just after the injected PFASs of interest.

SPE Method Overview Advantage: Sample Cleanup and Concentration, compatible with DOD QSM 5.1 Overview: Calibration and mass-labelled surrogate standards (i.e. isotope dilution stds) purchased from Wellington Laboratories (Guelph, ON); wide coverage for surrogates Surrogate standards (25 ng) spiked into 250 mL water samples PFAS compounds extracted and concentrated on weak anion-exchange SPE column (e.g. Phenomenex Strata® X-AW) Using Strata X-AW SPE sorbent tubes with a vacuum manifold keeps it compatible with the Department of Defense Quality Systems

And then EPA method 537 standards were purchased from Wellington Laboratories, who have a nice range of native, labelled, internal, and surrogate standards.

SPE Method: Flowchart 250 mL water sample, polyethylene bottle Spike with surrogate standards (25 ng), Wellington Laboratories Extraction with weak anion-exchange SPE column Rinse bottle with 10 mL of methanol with 0.3% NH4OH Elute PFAS with bottle rinsate, evaporate to near dryness 25ng of the surrogate standards from Wellington were spiked into a 250mL water sample in a polyethylene bottle - this container is also important to avoid any fluorinated polymer compositions. The entire volume is then loaded onto the Strata X-AW cartridge. The elution solvent, 0.3% ammonium hydroxide in methanol, was then swirled into the sample bottle, before using it to elute the PFASs into collection tubes. After evaporating down to a few microliters, they were reconstituted with 500uL of 80:20 methanol:water and transferred to polypropylene autosampler vials. Standards and blanks prepared with 80% methanol concentration Reconstitute with 500 μL of 80:20 Methanol:Water, transfer to polypropylene vials

LC Conditions For: SPE Method
HPLC Chromatographic separation was then performed on a 50 x 2mm Gemini 3u C18 column with an ammonium acetate in water gradient elution with methanol. With this SPE sample preparation yielding clean and concentrated analytes, elution after initial retention and focusing after injection at 10% methanol was accelerated with a quick step up to 55%methanol before a 4 minute gradient to 99% methanol.

Mass Spectrometer & Source Gas Conditions
SCIEX Triple Quad™5500 system with Turbo V™ source ESI probe in negative polarity mode Source parameters optimized using Compound Optimization (FIA) function in Analyst® software Parameter Value Curtain Gas (CUR) 35 psi IonSpray Voltage (IS) -4500 V Temperature (TEM) 600 oC Nebulizer Gas (GS1) 50 psi Heater Gas (GS2) Detection was performed on a Sciex 5500 Triple Quad with a TurboV ion-source using electrospray in negative ion-mode.

Mass Spectrometer Parameters: Compound Specific
Q1 Q3 DP CE PFCAs PFBA 212.9 169 -25 -12 PFPeA 262.9 219 -20 PFHxA 313 269 PFHpA 363 319 PFOA 413 369 -14 PFNA 463 419 PFDA 513 469 -16 PFUdA 563 519 -18 PFDoA 613 569 PFTrDA 663 619 PFTeDA 713 669 -22 PFHxDA 813 769 -24 PFODA 913 869 -26 Compound Q1 Q3 DP CE PFSAs PFBS 298.9 80 -55 -58 PFHxS 399 -60 -74 PFHpS 449 -65 -88 PFOS 499 -108 PFDS 599 -85 -118 Other PFASs 6:2 FTS 427 407 -50 -32 8:2 FTS 527 507 -40 PFOSA 498 78 MeFOSA 512 169 -75 -37 EtFOSA 526 N-MeFOSAA 570 419 -36 N-EtFOSSA 584 Mass analyzer tuning was optimized for each individual compound, which included their declustering potentials and collision energies. De-clustering Potential (DP) and Collision Energy (CE) optimized for each compound One MRM transition monitored each analyte and internal standard Scheduled MRMTM algorithm used to maximize dwell times and optimize cycle time

Chromatogram: 10 pg on-column injection
6.5 min run time! And then here you can see the nice selectivity of each analyte, including some of the branched isomers of interest eluting just before their linear counterparts. Overlaid chromatogram of 1 μg/L standard

Method Performance: Calibration Range, Sensitivity and Accuracy
Compound Calibration Range (ng/L) Linear Correlation (r2) S:N of 25 ng/L standard Accuracy of 25 ng/L standard PFCAs PFBA 25-20,000 0.997 108 104% PFPeA 0.998 88 103% PFHxA 104 93% PFHpA 0.999 116 101% PFOA 117 106% PFNA 0.990 91 109% PFDA 103 105% PFUdA 0.995 84 PFDoA 60 PFTrDA 32 PFTeDA 0.994 15 107% PFHxDA 21 PFODA 33 102% And along with the wide linear dynamic range, the high signal-to-noise ratios at the LOQ show sensitivity well below method requirements. 3 orders of linear dynamic range Excellent signal-to-noise and accuracy of lowest calibrator

Compound Calibration Range (ng/L) Linear Correlation (r2) S:N of 25 ng/L standard Accuracy of 25 ng/L standard PFSAs PFBS 25-20,000 0.995 31 92% PFHxS 0.999 604 103% PFHpS 0.997 103 105% PFOS 312 PFDS 0.998 88 102% Other PFASs 6:2 FTS 0.991 100 98% 8:2 FTS 0.992 113 97% PFOSA 118 104% MeFOSA 0.996 96 EtFOSA 0.994 90 101% N-MeFOSAA 109 100% N-EtFOSSA 61 The range and sensitivity gives a bit of method flexibility too 500x concentration factor: 25 ng/L injection std -> 0.05 ng/L in sample; method flexibility

SPE Method Application: Real-World Water Sample
* Chromatographic separation of isomers Here’s a real-world sample chromatogram, where you can again see some of the branched isomers resolving. Also, I wanted to mention here that you’re not seeing any system peaks from the delay column, because scheduled MRMs were used to maximize dwell times and optimize cycle time. Overlaid chromatogram of PFAS in water sample

SPE and LC/MS/MS - Method Summary
Sample cleanup and concentration, compatible with DOD QSM 5.1 Short 6.5 min LC method; separation of PFAS compounds and isomers with HLPC Good peak shape for lower chain-length PFAS Use of delay column to separate contamination from LC Method performance: 3 orders of linear dynamic range, +/- 10% accuracy and excellent S/N for lowest calibrator (25 ng/L), r2 >0.990 Applied to real-world water sample; PFAS detected at ng/L Can detect levels well below new EPA drinking water guidelines for PFOA and PFOS So in this case study, we demonstrated an SPE sample clean-up and concentration with HPLC-MS compatible with the DOD method, and can detect levels well below the new EPA drinking water guidelines for PFOA and PFOS.

PFAS using HPLC and Direct Inject LC/MS/MS Case Study 2
Craig Butt, Ph.D. Product Application Specialist

Large Volume Injection Method Overview
Advantage: Minimal sample preparation, reduced contamination potential Overview: Water samples diluted with methanol + surrogate standards Direct injection of 950 μL onto analytical column Longer and larger diameter column used to improve retention; resulting in longer runtime (17.5 min)

Large Volume Injection Method: Flowchart
1 mL water sample combined with 0.65 mL methanol + surrogate standards 950 μL injection on PAL HTC-xt autosampler

Method Overview Method not optimized for PFHxDA (C16) and PFODA (C18)
Presence of 5 g/L Trizma is not compatible with large volume injection method due to ionization suppression (but is compatible with SPE method) Mass Spectrometer: SCIEX Triple Quad™5500 system with Turbo V™ source; ESI negative mode Identical source gas and compound-specific parameters as the SPE method

LC Conditions For: Large Volume Injection

Chromatogram: Large Volume Injection Method
Overlaid chromatogram of 10 ng/L spike into groundwater

Compound Calibration Range (ng/L) Linear Correlation (r2) S:N of 1 ng/L standard Accuracy of 1 ng/L standard PFCAs PFBA 1-200 0.997 328 97% PFPeA 0.999 137 101% PFHxA 284 PFHpA 0.993 267 96% PFOA 113 99% PFNA PFDA 176 PFUdA 0.998 168 PFDoA 0.994 127 94% PFTrDA 0.995 125 95% PFTeDA 56 98% PFSAs PFBS 2-200 1178 100% PFHxS 229 PFHpS 327 PFOS 251 PFDS 516 PFOSA 1-100 1012

Large Volume Injection Method Application
*Chromatographic separation of isomers Overlaid chromatogram of PFAS in groundwater sample as analyzed by large volume injection

Large Volume Injection Method Summary
Minimal sample preparation; dilute with methanol + surrogate standard and inject (“dilute & shoot”) Method performance: 2 orders of linear dynamic range, +/- 10% accuracy and excellent S/N for lowest calibrator (25 ng/L), r2 >0.990 Excellent method robustness; precision (% CV) was <5% for 9 replicates (20 ng/L) over 1 week analysis Applied to real-world groundwater sample; PFAS detected at ng/L Can detect levels below EPA drinking water guidelines (70 ng/L for PFOS and PFOA)

PFAS using SPE or Direct Inject by UHPLC-MS/MS Case Study 3
Agustin Pierri, Ph.D. Technical Director

UHPLC Conditions For: Large Volume Injection and SPE

Direct Injection Chromatogram
23 PFAS Analytes 6:2 FTS 8:2 FTS EtFOSA MeFOSA FOSA EtFOSE MeFOSE PFBA PFBS PFDA PFDS PFHpA PFHpS PFHxA PFHxS PFNA PFOA PFOS PFPeA PFDoA PFTeDA PFTrDA PFUdA Less than 4 mins

PFAS in Butter, Egg, and Milk QuEChERS, SPE and LC-MS/MS Case Study 3
Dr. Agustin Pierri Two-step extraction procedure- QuEChERS and Solid Phased Extraction (SPE)- LC-MS/MS roQ QuEChERS Original Non-buffered We actually just finished the method validation using the two-step extraction procedure this week—The final procedure is below. We tested this out for milk, butter, eggs, and fish tissue. One thing I will talk about is that we have two approaches: one with just the quechers extraction, but using isotope dilution for analysis (method A), and one using surrogates and IS, but implementing the two extraction steps—quechers and SPE—method B. The attached chromatogram is the matrix spike in butter after extraction by method B. Let me know if this is what you needed, or if needed, I can add some more details. Now that the method is validated and all of the data I wanted is acquired, I can finally finish putting the talk together! Agustin The LC conditions are: Column: Luna Omega 1.6u PS C18 100x2.1 mm Mobile phase A: 5 mM ammonium acetate/water Mobile phase B: Acetonitrile Flow rate: 550 uL/min Injection volume: 2 uL Gradient: Time %B 0 40 0.5 40 3 90 3.1 100 4 100 Full extraction procedure: Mass 1 g sample into 50 ml plastic tube (Tubes included with KS0-8910) Spike samples with IS/surrogate and/or analytical spike as appropriate Add 10 ml acetonitrile & 10 ml water Add salt pack from KS0-8910 Caution: Exothermic Reaction Note: Salt pack will clump (vortexing is not violent enough to break clumps) Specifically shake the sample violently until homogenous and then vortex for 30 seconds Centrifuge until acetonitrile, water and solids layer all appear Note: Additional layers are possible depending on fat and protein content of samples. This also lead to variation in the time needed to centrifuge the samples. Remove 1 ml of acetonitrile and add to KS vials already containing dSPE salts Vortex for 30 seconds Centrifuge until salt pack is compacted on bottom vial and suspended solids settle Remove 1 mL clean acetonitrile, and either analyze if using method A, or dilute to ~15 mL with water if using method B Method B: Condition Strata-XAW 200mg/3mL SPE cartridge (8B-S038-FBJ) with 3 aliquots of 0.3% NH4OH/ACN Load diluted quechers extract Wash with 5 mL water Elute with 4 mL 0.3% NH4OH/ACN Blow down to 1 mL Spike with IS, and analyze

QuEChERS Protocol Add 1.0 gram homogenized sample to 50 mL tube
Add 10 mL H2O and 10 mL MeCN Add 4 g MgSO4 and 1 g NaCl Vortex 3 minutes, centrifuge 5 minutes Transfer 1 mL aliquot to tube with 150 mg MgSO4 and 50 mg PSA Transfer Aliquot for LC-MS/MS analysis Analysis was done using on Luna Omega PS C18 50 x 2.1mm LC-MS/MS roQ QuEChERS Original Non-buffered

QuEChERS and SPE Protocol
Add 1.0 grams homogenized sample to 50 mL tube Add 10 mL H2O and 10 mL MeCN Add 4 g MgSO4 and 1 g NaCl Vortex 3 minutes, centrifuge 5 minutes Transfer 1 mL aliquot to tube with 150 mg MgSO4 and 50 mg PSA Transfer 500 µL, dilute to ~15 mL with H2O for SPE SPE Condition Strata-XAW 200 mg/3 mL SPE cartridge with 0.3% NH4OH/MeCN Load diluted QuEChERS extract, wash with 5 mL H2O Elute with 4mL 0.3% NH4OH/MeCN Transfer 200 µL to conical vial for analysis Evaporate to 500 µL, transfer to conical vial for analysis Analysis was done using Luna Omega PS C18 50 x 2.1mm roQ QuEChERS Original Non-buffered LC-MS/MS

Extracts Blank Butter Cheese Egg Milk Fish

PFAS in Butter using SPE and LC-MS/MS
LUNA OMEGA PS C18 We would like to provide special thanks to Agustin Pierre from Weck Laboratories for contributing this application.

QuEChERS Recoveries, Egg
n=4, spiked at 2x the MRL: 100 ppt n=4, 1 ng/g

n=4, spiked at 2x the MRL: 10 ppt
n=4, 0.1 ng/g

Branched vs. linear PFBA PFHxS PFOS Solvent blank 👍 Isobars:

PFAS using Online SPE by HPLC-MS/MS Case Study 4
David Schiessel

Evaluation of Online SPE Sorbents for PFAS

Sample Prep Procedure Online SPE Program (pump 2) LC Gradient (pump 1)
1. Samples are collected in polypropylene bottles and preserved with 0.5 g/L Trizma®. 2. A 10 mL aliquot is spiked with surrogates at a concentration of 50 ng/L. 3. If necessary, filter using a 10 mL syringe fitted to a 1.2 μm glass fiber syringe filter. 4. The filtered sample is spiked with internal standard at 50 ng/L. 5. The filtered sample is loaded and analyzed using a 5.0 mL injection volume. 6. The online SPE is completely automated; it includes a sample wash step (2.1 to 4.1 min) to wash Trizma preservative from the media. Online SPE Program (pump 2) Time (min) Water (%) MeOH (%) AcN (%) Flow (mL/min) Step 0.00 100 2.5 Load 2.00 2.10 Wash 4.10 4.11 30 70 Idle 9.00 9.01 2.0 9.49 9.50 98 3.0 11.50 2..0 11.51 Equil 14.00 LC Gradient (pump 1) Time (min) Water (%) MeOH (%) 0.4% NH3 (%) 0.00 90 10 3.10 20 60 4.50 6.10 11.00 14.00 Note: to decrease PFOA contributed by the eluent system, MeOH is kept at 90 % while loading the online SPE with sample and subsequently brought down to 20 % 1 min prior to online SPE elution.

Evaluation of Online SPE Sorbents for PFAS

PFAS in Sediment using QuEChERS Case Study 5
Syljohn Estil and Eric Nelson

PFAS in Sediment using QuEChERS

Conclusion Solid Phase Extraction or Large-Volume Injection are both suitable sample preparation techniques Delay column to distinguish system related PFAS interferences HPLC and UHPLC column chemistries suitable for the chromatographic range of polar acids through non-polar acids, esters, amides, and sulfonamides with selectivity of branched vs. linear isomers SCIEXTriple Quad™ 5500 with Turbo V™ source Detection limits at low ppt levels with the ability to detect below drinking water guidelines And thank everyone for joining as we showed several successful strategies for LCMSMS determination of Per and polyfluorinated alkyl substances in water, compatible with the DOD method and able to detect low ppt levels below EPA drinking water guidelines.

Environmental Support and Resources
SPE Method Development Tool 1,000s of Applications On-Site Lab Demos Environmental Edge Newsletter Technical Notes Digital Learning Tutorials I also wanted to point out the range of Environmental support tools and resources available on our website 59

Thank You Acknowledgements
We would like to provide special thanks to Dr. Craig Butt and Dr. Simon Roberts at SCIEX, Dr. Agustin Pierri from Weck Laboratories, Syljohn Estil at Sanitation Districts of LA, and David Schiessel at BABCOCK Laboratories, for their contributions. And again, special thanks to Dr. Craig Butt from Sciex and Dr. Agustin Pierri from Weck Laboratories for their contributions and expertise. Trademarks and Disclaimers Luna, Gemini, and Strata are registered trademarks of Phenomenex. Turbo V and Triple Quad are trademarks of AB SCIEX Pte. Ltd. AB SCIEX™ is being used under license. © 2018 Phenomenex, Inc. All rights reserved.

Scott Krepich Senior Field Application Scientist

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