Frank L. Dorman The Pennsylvania State University Department of Biochemistry and Molecular Biology

Transcription

1 Frank L. Dorman The Pennsylvania State University Department of Biochemistry and Molecular Biology

2 Coauthors and Collaborators Jack Cochran, Shawn Reese Restek Corporation Eric Reiner, Karen Macpherson, Terry Kolic Ontario ministry of Environment

3 Dioxin and Furan Analysis Dual column method Usually 5% diphenyl column and a high-cyano column (eg Rtx-225) Cyano columns have poorer lifetimes and lower maximum operating temperatures 5% diphenyl phases do not have the selectivity to accurately quantitate most samples USEPA requires 2,3,7,8-tcdf to be confirmed on a X-225 Desirable to have both columns in the same oven, and to improve the separation of the 5, or employ a single column which achieves the necessary separation

4 PCDD and PCDF Target List # of Chlorine #Dioxins #Furans tetra 22(1) 38(1) penta 14(1) 28(2) hexa 10(3) 16(4) hepta 2(1) 4(2) octa 1(1) 1(1) ( ) numbers are 2,3,7,8-substituted congeners

5 Tetra-dioxin resolution check standard on 5% diphenyl / 95% dimethyl stationary phase / Jul21_ : Voltage SIR 20 Channels EI e5 % M X 0.25 mm i.d. X 0.25 um d.f. Time

6 How Resolution Affects Quantitation Quantification of 20 ppb Reference Standard (Results Based on Multilevel/Multi-component Calibration): Component A Component B Component A & B Rep Rep Rep Component A Rep Rep Rep Component B Rep Rep Rep

7 Effect of coelution: 2,3,7,8-TCDF (pg/g) Certified 5% phenyl Value WMS EC-2(DX-1) ( 44) Sediment NIST Flyash Flyash Biota Biota

8 Achieving Analyte Separation Resolution R = 1/4 L / h x ( k / k +1 ) x ( a-1 / a ) Capacity Factor K = t R - t 0 / t 0 Selectivity a = k 2 / k 1 Thermodynamics: DG = DH - TDS DG = - RT ln K D

9 O 41 Cl Cl Cl S O Cl O Cl Cl Cl Cl Cl Cl Cl Endosulfan a Chlordane (mainlib) Chlordane 252 Cl 229 Cl Cl inlib) 9Endosulfan

10 Which should be more selective? CH Si O Si O CH 3 3-5, -35, etc CH -OR- 3 CF 3 C H 2 4 Si O Si O Si O CH 3 CH 3 10

11 Alpha chlordane and Endosulfan I 30 M X 0.25 mm i.d. X 0.25 um d.f. 1.0 ml/min, 100 C (1), 10 C/min to 300C Rtx-5 Rtx-35 Rtx-CLP2 mm x 0.25 µm Flow : 1.00 ml/min R= R= R= ) 11

12 Modeling - Energies of Interaction F F H 3 C O Si O Si CH 3 F F DG DG Cl Cl Cl O O O O Cl Cl Cl Cl Cl F Si O F Separation (Da) = D DG

13 3-Space Selectivity Model for 3 Compounds Surface=FDHDS

14 / Tetra-dioxin resolution check standard on 5% diphenyl / 95% dimethyl stationary phase Jul21_ : Voltage SIR 20 Channels EI e5 % M X 0.25 mm i.d. X 0.25 um d.f. Time

15 Rtx-Dioxin2 Capillary GC Column 60-M X 0.25 mm i.d. X 0.25 um d.f TCDD Resolution Mix 1238/

16 Success of Modeling Approach Depends on accuracy of Input Data Accuracy of chromatographic variables Correctly solving for energy state minima Model may need to be refined Based on experimental agreement to prediction Requires chromatographic analysis of targets AND possible co-eluting compounds

17 may06_cs5 x4 100 TCDD Dioxin Window Voltage SIR 14 Channels EI e6 % 0 may06_cs5 100 % PCDD Voltage SIR 14 Channels EI e6 0 may06_cs5 100 % HxCDD Voltage SIR 14 Channels EI e6 0 may06_cs5 100 % HpCDD Voltage SIR 14 Channels EI e5 0 may06_cs5 100 % OCDD Voltage SIR 14 Channels EI e Time

18 may06_cs5 100 % TCDF Furan Window Voltage SIR 14 Channels EI e5 0 may06_cs5 100 % PCDF Voltage SIR 14 Channels EI e6 0 may06_cs5 100 % 0 may06_cs5 100 % HxCDF HpCDF Voltage SIR 14 Channels EI e6 Voltage SIR 14 Channels EI e6 0 may06_cs5 100 % OCDF Voltage SIR 14 Channels EI e Time

19 Effect of Resolution: 2,3,7,8-TCDF (pg/g) Certified 5% phenyl X-225 Rtx-DIOXIN2 Value WMS EC-2(DX-1) 88 n/a ( 44) Sediment NIST n/a Flyash Flyash Biota Biota

20 Resolution: 1,2,3,4,7,8-HxCDF (pg/g) Certified 5% phenyl Rtx-Dioxin2 Value WMS EC-2 (DX-1) ( 276) Sediment Flyash Flyash

21 Not so fast

22 Data Summary 14 of 17 toxic 2378 congeners separated from all possible interferences All 136 possible pcdd and pcdf (4-8 Cl) congeners became available after column development was completed 3 second retention time difference is separation Not baseline resolved Baseline resolution not required for EPA Methods Extreme concentration differences might lead to quantification bias for limited number of 2378s Further chromatographic optimization will improve separations

23 2378 Coelutions on Rtx-Dioxin and PnCDDs Particularly serious because WHO-TEF for PnCDD is 1 (same as 2378 TCDD) and HxCDFs Magnitude of quantification bias depends on sample type not always observed and HxCDFs Quantification bias sometimes high

24 % FLYASH-C APRIL FLYASH-END Sm (Mn, 2x2) : Voltage SIR 10 Channels EI e TCDDs on Rtx-Dioxin Time

25 % FLYASH-C APRIL FLYASH-END Sm (Mn, 2x2) 100 TCDFs on Rtx-Dioxin : Voltage SIR 10 Channels EI e Time

26 2378 TCDF in fly ash on Rtx-Dioxin2 under different GC conditions Flow and temperature program optimization can improve separations

27 % FLYASH-C APRIL FLYASH-END PnCDFs on Rtx-Dioxin2 2: Voltage SIR 8 Channels EI e Time

28 23478 PnCDF WHO-TEF of 0.5 The PCDD/PCDF distribution is dominated by PnCDF, 2378 TCDF, and HxCDF Chloralkali process Shown by Ryan to coelute with 12489, 12679, and on 5% diphenyl Fishman suggested multiple coelutions on 5% diphenyl and all other columns, except high cyano content columns (225, 2331) Cochran shows coelution with on 5% diphenyl

29 23478 PnCDF Quantification (pg/g) Sample 5% Ph Rtx-Dx2 Cert Sediment Sediment Sediment Fly ash Fly ash

30 PnCDDs on Rxi-5ms Time (s) S1 20m x 0.18mm x 0.18µm

31 HxCDFs on Rxi-5ms Time (s) S1 20m x 0.18mm x 0.18µm

32 Fishman, Martin, Lamparski Column Sets for 2378 Separations D/F 5% Ph X X X X X X X X 2378 X X X X X X X X D/F 5% SP X X X X X X X X X X 2378 X X X X X X X X X

33 Fishman, Martin, Lamparski Column Sets for 2378 Separations D/F 5% Ph 225 D/F 5% SP X X 2378 X X X X X X X X X X X X X X X X The high cyano content columns (225 and 2331) 2378 X separate PnCDF X X X X X 2378 X X X X The temperature limits for the 225 and 2331 columns X X X are only 220 C and 275 C, respectively X X X X

34 Another suggestion for two column set 5% diphenyl (Rxi-5ms) and Rtx- Dioxin2 Separates all 17 toxic 2378 congeners Thermal stability to 350 C and 340 C Eliminates need for less thermally stable, high cyano columns D/F 5% Ph Dioxin X X X X X X X X 2378 X X X X X X X X X

35 Conclusions 136 tetra- through octa- chlorinated dioxins and furans allowed full GC column characterization Congeners commercially available Rtx-Dioxin2 is specific for 2378 TCDD and TCDF Eliminate non-rugged, low-temperature cyano columns Two robust GC columns can separate all 17 toxic 2378 congeners for most samples Rxi-5ms (thermally stable to 350 C) Rtx-Dioxin2 (thermally stable to 340 C) Hopefully we may now be able to determine a single column chemistry that provides a single column solution

36 Acknowledgements: Thermo Scientific Kyle D Silva Jack Cochran Karen MacPherson Penn State University

37 Thank You Questions?