Method Development of a 2D LC-HRMS Extraction and Detection Method for Organophosphorus Flame Retardants in Environmental Water Samples

Transcription

1 Method Development of a 2D LC-HRMS Extraction and Detection Method for Organophosphorus Flame Retardants in Environmental Water Samples Ken Rosnack 1 Lauren Mullin 1,2, Malorie Mella 1, Claude Mallet 1, Doug Stevens 1, Ingrid Ericson Jogsten 2, Gareth Cleland 1 1 Waters Corporation, 34 Maple Street, Milford, MA 01757,USA 2 MTM Research Centre, Örebro University, Örebro Sweden 2017 Waters Corporation 1

2 Overview Introduction 2D LC QTof overview Method optimization Sample results 2017 Waters Corporation 2

3 Introduction Compounds used as flame retardants and plasticizers in various materials K ow ranges 1.71 to 9.0 Non-covalently bound to products = potential for environmental occurrence Sample analysis incorporating various sample preparation approaches Dry down and solvent exchange common Targeted Goal: Implement direct injection of organic solvents + utilize full spectrum acquisition with accurate mass data to identify targeted and non-targeted OPFRs 2017 Waters Corporation 3

4 System Overview 2017 Waters Corporation 4

5 System Layout FTN CMA BSM Loader/Diluter BSM Eluter 2017 Waters Corporation 5

6 At-Column Dilution (ACD) Flow Path MS Injector Loop waste D1 Trapping Dimension D2 Resolving Dimension Separation Chemistries 1.7mm particle size A BSM Pump B Loader/Diluter BSM Pump Eluter Trapping Chemistries 10-20mm particle size Loading Conditions Eluting Conditions 2017 Waters Corporation 6

7 Why QTof? QQQ Vs HRMS MRM #1 MRM #4 MRM #6 MRM #3 MRM #5 MRM #7 MRM # Waters Corporation 7

8 Analyte Selectivity: Triple Quad vs TOF Triple Quad MRM/SRM Precursor to Fragment ion transmission Compound specific transition Analytes defined in method development Methods redeveloped for new compounds TOF Selectivity from mass resolution Data can be re-interrogated Quadrupole and TOF Resolution 2017 Waters Corporation 8

9 Xevo G2-XS QTof MS E Acquisition Mode Fragmentation in the XS collision cell alternate scans Combined Data High Energy Data Low Energy Data Ionization Mode: ESI + Acquisition Range: m/z Acquisition Rate: 8 spectra/sec Capillary: 0.80 kv Source Temp: 120 C Desolvation Temp: 550 C Cone Gas: 50 L/hr Desolvation Gas: 1000 L/hr Cone Voltage: 20 V Acquisition Conditions Collision Energy (LE): 4 V Collision Energy (HE Ramp): 10 to 45 V Lockspray: Leu Enk ( ) Acquisition Conditions 2017 Waters Corporation 9

10 Method Development 2017 Waters Corporation 10

11 Loading ph Loading ph Loading ph 2D Optimization Scheme 3x3 Method Optimization (9 permutations) 10 min LC Run Time / 4.5 hours 3x6 Method Optimization (18 permutations) 10 min LC Run Time / 9 hours 7 C8 ph 10 Loading ph 3 ACN Elution 8 C18 ph 10 Loading ph 3 ACN Elution 9 HLB ph 10 Loading ph 3 ACN Elution C8 16 ph 10 Loading ph 10 ACN Elution C18 17 ph 10 Loading ph 10 ACN Elution HLB 18 ph 10 Loading ph 10 ACN Elution C8 4 ph 7 Loading ph 3 ACN Elution C18 5 ph 7 Loading ph 3 ACN Elution HLB 6 ph 7 Loading ph 3 ACN Elution C8 13 ph 7 Loading ph 10 ACN Elution C18 ph 7 Loading ph 3 ACN Elution 14 HLB 15 ph 7 Loading ph 10 ACN Elution C8 1 ph 3 Loading ph 3 ACN Elution C18 2 ph 3 Loading ph 3 ACN Elution Trap Retention Strength 3 HLB ph 3 Loading ph 3 ACN Elution C8 10 ph 3 Loading ph 10 ACN Elution C18 11 ph 3 Loading ph 10 ACN Elution Elution ph HLB 12 ph 3 Loading ph10acn Elution 25 C8 ph 10 Loading ph 3 MeOH Elution 26 C18 ph 10 Loading ph 3 MeOH Elution 27 HLB ph 10 Loading ph 3 MeOH Elution 34 C8 ph 10 Loading ph 10 MeOH Elution 35 C18 ph 10 Loading ph 10 MeOH Elution 36 HLB ph 10 Loading ph 10 MeOH Elution C8 22 ph 7 Loading ph 3 MeOH Elution 19 C8 ph 3 Loading ph 3 MeOH Elution C18 23 ph 7 Loading ph 3 MeOH Elution C18 20 ph 3 Loading ph 3 MeOH Elution HLB 24 ph 7 Loading ph 3 MeOH Elution 21 HLB ph 3 Loading ph 3 MeOH Elution Elution Polarity 2 analytical columns: BEH C 18 and BEH Phenyl C8 31 ph 7 Loading ph 10 MeOH Elution C8 28 ph 3 Loading ph 10 MeOH Elution C18 32 ph 7 Loading ph 10 meoh Elution C18 29 ph 3 Loading ph 10 MeOH Elution HLB 33 ph 7 Loading ph 10 MeOH Elution HLB 30 ph 3 Loading ph 10 MeOH Elution 2017 Waters Corporation 11

12 Chromatography Results: Trap Retention Strength and Elution Polarity Tailing with increasing retention strength of trap when MeOH is used for organic mobile phase Ex. Cresyl diphenyl phosphate (DCP) MW: Impacts Earlier Eluters: TCEP, V6, TCDPP, TPhP and TBP Methanol Acetonitrile C 18 ph 3 loading 2017 Waters Corporation 12 HLB

13 Chromatography Results: Loading ph Impact Tailing with ph 10 loading (organic mobile phase independent) Ex. Tris (2-isopropyl phenyl) phosphate (IPPP) MW: Acetonitrile C 18 Impacts Later Eluters: EDHP, IDPP, TBNPP HLB ph 3 loading ph 10 loading 2017 Waters Corporation 13

14 Chromatographic Peak Height Analyte Response Variation by 2D Method 1.00E+08 OPFR 2D Response Optimizations: Phenyl Chromatographic Column EHDP 1.00E+07 DCP IDPP 1.00E+06 V6 TBP 1.00E+05 TPP TDCPP 1.00E+04 TCEP IPPP 1.00E+03 Acetonitrile Elution (2 nd D) Methanol Elution (2 nd D) D Condition TBNPP 2017 Waters Corporation 14

15 Solvent Na + Adducting Trends: Higher for Methanol MP B [M+H] + [M+Na] + Methanol MP B Acetonitrile MP B 2017 Waters Corporation 15

16 Optimum Chromatography Method Results Loading Conditions Column: XBridge C 18 Direct Connect HP, 2.1 x 30 mm, 10µm Loading: MilliQ Water (ph 3) Flow Rate: 2 ml/min ACD: 5% (0.1 ml/min loading pump and 2mL/min diluting pump UPLC Conditions System: ACQUITY UPLC I-Class BSM configured for Trap and Elute with ACD Runtime: 10 min Column: ACQUITY UPLC BEH Phenyl, 2.1 x 50 mm, 1.7µm Column Temp: 50 C MP A: Water + 0.5% formic acid MP B: Acetonitrile + 0.5% formic acid Gradient: 6 minute linear from 5% (B) to 95% (B) Flow Rate: 0.5 ml/min (Elution pump) Injection Volume: 100µL in acetonitrile TBNPP 7.65 min. IPPP 7.51 min. IDPP 7.26 min. EDHP 7.00 min. DCP 6.60 min. TPhP 6.44 min. TBP 6.30 min. TCDPP 6.45 min. Valve switch to chromatography column TCEP 5.43 min. V min. Chromatography gradient 2017 Waters Corporation 16

17 MS E fragments 2017 Waters Corporation 17

18 Limit-of-Detection/Quantification LOD S/N PtP 3:1 LOQ S/N PtP 10:1 Both: at least 1 fragment ion confirmation TPP, TDCPP and DCP excluded as levels observed in blank at lowest cal. point 2017 Waters Corporation 18

19 Sample Introduction 2017 Waters Corporation 19

20 Sample Preparation: SPE Previous methodologies for various OPFRs have utilized SPE successfully in environmental water samples Simplified version adopted in with dry-down step eliminated Steps: Rinse needles with methylene chloride Affix Oasis HLB cartridge (6cc 150 mg) to extraction manifold Wash 5mL MeOH, 5mL water Load sample (100mL) Elute 5mL ph 3 acetonitrile Inject 100uL acetonitrile extraction 2017 Waters Corporation 20

21 Targeted Identification IDPP, in both snow samples Identification criteria Mass error: +/- 5 ppm mass error Fragment mass confirmation 2017 Waters Corporation 21

22 Identifying Non-Targeted Compounds: Common Fragments Possibility of other OPRFs and plasticizers Full spectral acquisition=non-targeted acquisition for low and high collision energy -PO 4 (+4H) common structure and other common fragments 2017 Waters Corporation 22

23 Non-targeted identifications Additional compounds found with common fragments, ordered by most intense response 2017 Waters Corporation 23

24 Database Search for ID Tris(2-butoxyethyl) phosphate (TBEP) 2017 Waters Corporation 24

25 Conclusions 2D LC technology provides ability to inject large volumes of organic solvents without peak shape compromise Sensitive detection of OPFRs is possible with this large volume injection approach combined with Qtof detection Non-targeted data acquisition coupled with accurate mass measurement affords the ability to search for additional constituents in samples Future Direction Revisit sample prep method Biological and other environmental sample analysis 2017 Waters Corporation 25

26 References and Acknowledgements 1. G. Santin et al. J. Chromtogr. A 1441 (2016) X. Wang et al. J. Chromtogr. A 1218 (2011) H. Wolshke et al. Environmental Pollution (2015) D. Chen et al. J. Chromtogr. A 1220 (2012) S. Chu et al. Analytica Chimica Acta 885 (2015) J. Regnery et al. Clean 37 (2009) Thank You!! 2017 Waters Corporation 26