Simply GCxGC GC GC Made Simple and Easy to Use

Transcription

1 Simply GCxGC GC GC Made Simple and Easy to Use LECO Webinar July 19, 2017 Mark Merrick Steve Robles, Kevin McNitt, Todd Richards, Joe Binkley LECO Corporation Leonid Blumberg Advachrom

2 Outline Introduction to GC GC Why GC GC? The method development challenge What are we optimizing? Simply GCxGC a method development tool

3 What is GC GC?

4 What is GC GC? Sample Inlet Modulator continuous, periodic injection of column 1 effluent into column 2 Detector (ToF-MS) 1 st Dimension Column (non-polar separation) 2 nd Dimension Column (polar separation)

5 What is GC GC?

6 What is GC GC? Detector First Dimension Column Modulator Second Dimension Column

7 What is GC GC? Sampling Mode

8 What is GC GC? Release Mode

9 What is GC GC?

10 What is GC GC?

11 What is GC GC?

12 What is GC GC?

13 What is GC GC?

14 What is GC GC? Slice 3 Slice 2 Slice 1

15 What is GC GC? Signal Intensity 3D Plot 1st Column Retention Time Slice Number 5 6 2nd Column Retention Time Contour Plot

16 Why GC GC? Peak capacity Structured chromatograms Class selectivity

17 Why GC GC? Peak Capacity Diesel st Time (s) 2nd Time (s) TIC

18 Why GC GC? Peak Capacity Diesel Peak Capacity Fact The GC peak capacity increase from a 30 m x 0.25 mm column to a 120 m x 0.25 mm column is only 2-fold increase 1st Time (s) 2nd Time (s) TIC Peak Capacity Fact GC GC has the potential to achieve a 10-fold peak capacity gain over GC with same analysis time

19 Why GC GC? Structured Chromatograms Diesel GC no structure st Time (s) 2nd Time (s) TIC GC GC structure that can aid in classification and identification

20 Why GC GC? Class Selectivity Courtesy of Jack Cochran

21 I hate GC GC!!! Is it possible for GC GC to be simple and easy to use? Where do I start??? What s the objective? Selectivity? Peak Capacity? Both? Neither? Target Analysis? Non-Target Analysis? Column Dimensions? Flow rate? Heating rate? Temperature offsets? Method development? Software features? 1 st dimension phase? 2 nd dimension phase? Nonpolar/polar? Polar/nonpolar? Data analysis? Analytical information?

22 What are we optimizing? Optimized Peak Capacity (resolution) Column dimensions and conditions (flow,heating rate, modulation period, reinjection) Based on Blumberg s work these parameters can be calculated. Optimized Selectivity Stationary phases and order of phases Selection and order of stationary phases done by Examples in the literature Knowledge of stationary phases and sample Systematic experimentation Non-polar x polar Polar x non-polar

23 Logic of Optimizing Peak Capacity 6.5e+006 6e+006 Optimize first dimension. This is where you have the most resolving power and speed. 30 m x 0.25 mm 5.5e+006 5e e+006 4e+006 Time (s) TIC Determine modulation period to preserve 1 st dimension Time (s) st Time (s) nd Time (s) P m = 1.1 sec Adjust secondary oven offset and Column 2 length to fit 2 nd dimension Modulation period is length of 2 nd dimension separation

24 Optimum Peak Capacity Leon Blumberg in collaboration with LECO created a computational engine that computes column dimensions, operating conditions and peak capacities. At PittCon 2016 and Riva 2016 LECO presented validation data on a prototype software tool using this engine.

25 Simply GCxGC The Wizard Took the peak capacity computational engine and put it into a method development scheme and turned it into a wizard. START GCxGC Method Development Scheme DONE GOOD Select Column 1 Dimensions BAD Evaluate Stationary Phases GOOD Evaluate Peak Capacity BAD Calculate Column 2 and Conditions Select Stationary Phases Determine Secondary Oven Offset and Col. 2 Length

26 Simply GCxGC The Wizard Took the peak capacity computational engine and put it into a method development scheme and turned it into a wizard. START GCxGC Method Development Scheme DONE GOOD Select Column 1 Dimensions BAD Evaluate Stationary Phases GOOD Evaluate Peak Capacity BAD Calculate Column 2 and Conditions Select Stationary Phases Determine Secondary Oven Offset and Col. 2 Length

27 Simply GCxGC The Wizard Took the peak capacity computational engine and put it into a method development scheme and turned it into a wizard. START GCxGC Method Development Scheme DONE GOOD Select Column 1 Dimensions BAD Evaluate Stationary Phases GOOD Evaluate Peak Capacity BAD Calculate Column 2 and Conditions Select Stationary Phases Determine Secondary Oven Offset and Col. 2 Length

28 Simply GCxGC The Wizard Took the peak capacity computational engine and put it into a method development scheme and turned it into a wizard. START GCxGC Method Development Scheme DONE GOOD Select Column 1 Dimensions BAD Evaluate Stationary Phases GOOD Evaluate Peak Capacity BAD Calculate Column 2 and Conditions Select Stationary Phases Determine Secondary Oven Offset and Col. 2 Length

29 Simply GCxGC The Wizard Took the peak capacity computational engine and put it into a method development scheme and turned it into a wizard. START GCxGC Method Development Scheme DONE GOOD Select Column 1 Dimensions BAD Evaluate Stationary Phases GOOD Evaluate Peak Capacity BAD Calculate Column 2 and Conditions Select Stationary Phases Determine Secondary Oven Offset and Col. 2 Length Experimental

30 Simply GCxGC The Wizard Took the peak capacity computational engine and put it into a method development scheme and turned it into a wizard. START GCxGC Method Development Scheme DONE GOOD Select Column 1 Dimensions BAD Evaluate Stationary Phases GOOD Evaluate Peak Capacity BAD Calculate Column 2 and Conditions Select Stationary Phases Determine Secondary Oven Offset and Col. 2 Length

31 Simply GCxGC The Wizard Took the peak capacity computational engine and put it into a method development scheme and turned it into a wizard. START GCxGC Method Development Scheme DONE GOOD Select Column 1 Dimensions BAD Evaluate Stationary Phases GOOD Evaluate Peak Capacity BAD Calculate Column 2 and Conditions Select Stationary Phases Determine Secondary Oven Offset and Col. 2 Length

32 Simply GCxGC

33 Convert 1D to GC GC START GCxGC Method Development Scheme DONE GOOD Select Column 1 Dimensions BAD Evaluate Stationary Phases GOOD Evaluate Peak Capacity BAD Calculate Column 2 and Conditions Select Stationary Phases Determine Secondary Oven Offset and Col. 2 Length

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35 Tool is specific to LECO s TOFMS Systems. A reinjection width of 10 ms at FWHH is used.

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41 Stationary Phase Combinations START GCxGC Method Development Scheme DONE GOOD Select Column 1 Dimensions BAD Evaluate Stationary Phases GOOD Evaluate Peak Capacity BAD Calculate Column 2 and Conditions Select Stationary Phases Determine Secondary Oven Offset and Col. 2 Length

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44 Stationary Phase Combinations Basic recommendations are provided Primary column for difficult separations, isomers for example Secondary column for functionality differences Reversing phases can be very helpful Keep in mind maximum temperature of each phase Use your 1D GC knowledge

45 Evaluate Sample Loading START GCxGC Method Development Scheme DONE GOOD Select Column 1 Dimensions BAD Evaluate Stationary Phases GOOD Evaluate Peak Capacity BAD Calculate Column 2 and Conditions Select Stationary Phases Determine Secondary Oven Offset and Col. 2 Length Experimental

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47 Evaluate Sample Loading Think 1D GC Best to look at the chromatogram and not the contour plot

48 Determine Secondary Oven Offset START GCxGC Method Development Scheme DONE GOOD Select Column 1 Dimensions BAD Evaluate Stationary Phases GOOD Evaluate Peak Capacity BAD Calculate Column 2 and Conditions Select Stationary Phases Determine Secondary Oven Offset and Col. 2 Length Experimental

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50 Logic of Optimizing Peak Capacity 6.5e+006 6e+006 Optimize first dimension. This is where you have the most resolving power and speed. 30 m x 0.25 mm 5.5e+006 5e e+006 4e+006 Time (s) TIC Determine modulation period to preserve 1 st dimension Time (s) st Time (s) nd Time (s) P m = 1.1 sec Adjust secondary oven offset and Column 2 length to fit 2 nd dimension Modulation period is length of 2 nd dimension separation

51 Adjustment of Retention in 2 nd Dimension Key to scheme 4 Ways to adjust retention in 2 nd dimension First adjustment is secondary oven offset temperature (quick and easy) Second adjustment is column 2 length in the secondary oven (remove or add loops, relatively quick and easy) Third adjustment is film thickness of column 2 (need to change column) More retention, increase film thickness; less retention, decrease film thickness Desired film thickness may not be available Guidance on this needs to be added to the tool Fourth adjustment is heating rate (not in tool)

52 Run Optimized Conditions: +5, +40 Process data, confirm no wrap around Ignore peaks of blank and bleed Locate last eluting analyte in 2 nd dimension Last Eluting Analyte in 2 nd Dimension

53 Modulation Period (P m ) + Void Time ( 2 t m ) Void time is empty space you can use Fit 2 nd dimension separation into P m + 2 t m Optimum Modulation Period + Void Time Optimum Modulation Period Void Time

54 Three Cases of Retention in 2 nd Dim. Three cases for +5 and +40 offsets Evaluate retention time of last eluting analyte in 2 nd dimension (1) Too little retention - +5 and +40 results elute before modulation period + void time Increase length of secondary column (2) Too much retention - +5 and +40 results elute after modulation period + void time Decrease length of secondary column (3) Desired retention +5 result is greater than the modulation period + void time +40 result is less than the modulation period + void time Tool calculates the required offset

55 (1) Too Little Retention at +5 Where s last eluting peak in 2 nd dimension? Too much retention or too little retention? +5 Offset Too Little Retention Optimum Modulation Period + Void Time Optimum Modulation Period

56 (1) Too Little Retention at +40 Where s last eluting peak in 2 nd dimension? Too much retention or too little retention? +40 Offset Too Little Retention Optimum Modulation Period + Void Time Optimum Modulation Period

57 Modulation Period + Void Time

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60 (2) Too Much Retention Where s last eluting peak in 2 nd dimension? Too much retention or too little retention? +40 Offset Too Much Retention Optimum Modulation Period + Void Time Optimum Modulation Period

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63 (3) Retention in Between, +5 too much Where s last eluting peak in 2 nd dimension? Too much retention or too little retention? Optimum Modulation Period + Void Time +5 Offset Too Much Retention Optimum Modulation Period

64 (3) Retention in Between, +40 too little Where s last eluting peak in 2 nd dimension? Too much retention or too little retention? Optimum Modulation Period + Void Time +40 Offset Too Little Retention Optimum Modulation Period

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67 (3) Retention in Between, +7 Just Right Run predicted offset at optimum P m Confirm Optimum Modulation Period +7 Offset Void Time

68 (3) Retention in Between, +7 Shift 2 nd dimension axis to void time Last eluting analyte now on top Optimum Modulation Period + Void Time +7 Offset

69 Secondary Column Film Thickness Third choice in adjustment of retention in second dimension If you can t adjust with secondary oven offset or secondary column length, change film thickness. Go back to start and repeat process with different film thickness.

70 Diesel on 5 x 17 Column Set 5 C offset w 0.3m 17 column 40 C offset w 0.3m 17 column

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73 Diesel on 5 x 17 Column Set 5 C offset w 0.45m 17 column 40 C offset w 0.45m 17 column

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76 Diesel on 5 x 17 Column Set 5 C offset w 0.6m 17 column 40 C offset w 0.6m 17 column

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79 Diesel on 5 x 17 Column Set, +12 C

80 Evaluate Stationary Phases START GCxGC Method Development Scheme DONE GOOD Select Column 1 Dimensions BAD Evaluate Stationary Phases GOOD Evaluate Peak Capacity BAD Calculate Column 2 and Conditions Select Stationary Phases Determine Secondary Oven Offset and Col. 2 Length

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82 Evaluate Stationary Phases Evaluate primarily spread of peaks not resolution. However, look at difficult separations. Evaluate 1 st and 2 nd dimensions. Example courtesy of Jack Cochran

83 Evaluate Stationary Phases Poor stationary phase combinations cannot be fixed by column dimensions and conditions. Narrow band of peaks is not good. If you see this, change stationary phases. Like 1D GC, it s a judgement call. Is it good enough?

84 Evaluate Stationary Phases If bad, go back and install different stationary phase(s) reverse, change one, or change both. START GCxGC Method Development Scheme DONE GOOD Select Column 1 Dimensions BAD Evaluate Stationary Phases GOOD Evaluate Peak Capacity BAD Calculate Column 2 and Conditions Select Stationary Phases Determine Secondary Oven Offset and Col. 2 Length

85 Evaluate Stationary Phases Reversing phases can have a very significant effect. Think 1D GC. Rxi-5MS/Rxi-17SilMS Rxi-17SilMS/Rxi-5MS

86 Diesel on 5 x 17 Column Set, +12 C

87 Evaluate Peak Capacity START GCxGC Method Development Scheme DONE GOOD Select Column 1 Dimensions BAD Evaluate Stationary Phases GOOD Evaluate Peak Capacity BAD Calculate Column 2 and Conditions Select Stationary Phases Determine Secondary Oven Offset and Col. 2 Length

88 Evaluate Peak Capacity You have accepted the stationary phases, now focus on resolution (peak capacity). Evaluate each dimension. Differentiate problems that can be fixed by peak capacity from those that require stationary phase change. Even though you have accepted the stationary phases, you can still reject. The tool will give you choices if more peak capacity is desired. Or, just go back to beginning and put in longer first column.

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90 Evaluate Peak Capacity 1 st Dim. Evaluate data from optimum modulation period. Contour plot for first dimension. Look in more isolated areas for typical peak width, then examine congested area. Good Bad

91 Evaluate Peak Capacity 2 nd Dim. Select areas in contour plot, then look at the chromatogram. Look at less congested areas to see peak widths, more congested areas to check resolution and deconvolution st Time (s) 2nd Time (s) Spectrum #

92 Evaluate Peak Capacity 2 nd Dim. Select areas in contour plot, then look at the chromatogram. Look at less congested areas to see peak widths, more congested areas to check resolution and deconvolution B st Time (s) 2nd Time (s) Spectrum #

93 Increase Peak Capacity START GCxGC Method Development Scheme DONE GOOD Select Column 1 Dimensions BAD Evaluate Stationary Phases GOOD Evaluate Peak Capacity BAD Calculate Column 2 and Conditions Select Stationary Phases Determine Secondary Oven Offset and Col. 2 Length

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95 Increase Peak Capacity Increase overall peak capacity Slow down same column set, slower heating rate, longer modulation period Lengthen columns Next available length or union of two lengths Longer column faster than slow down for same peak capacity Or, go back to beginning

96 Increase Peak Capacity Increase overall peak capacity with slow down Optimum Heating Rate Slow Down of Heating Rate 30x0.25x0.25/0.6x0.25x /min 30x0.25x0.25/0.6x0.25x /min

97 Increase Secondary Column Peak Capacity START GCxGC Method Development Scheme DONE GOOD Select Column 1 Dimensions BAD Evaluate Stationary Phases GOOD Evaluate Peak Capacity BAD Calculate Column 2 and Conditions Select Stationary Phases Determine Secondary Oven Offset and Col. 2 Length

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99 Increase Secondary Column Peak Capacity Wide/Narrow bore increases peak capacity in secondary column Up side is large increase in peak capacity Down side is slower and less loadability

100 Increase Secondary Column Peak Capacity Same ID, Optimum Heating Rate Narrower Col. 2 and Slow Down 30x0.25x0.25/0.6x0.25x /min 30x0.25x0.25/0.9x0.1x /min

101 Increase Secondary Column Peak Capacity Like one-dimensional GC slower produces more peak capacity Same ID, Optimum Heating Rate Narrower Col. 2 and Slow Down 30x0.25x0.25/0.6x0.25x /min 30x0.25x0.25/0.9x0.1x /min

102 Decrease Run Time START GCxGC Method Development Scheme DONE GOOD Select Column 1 Dimensions BAD Evaluate Stationary Phases GOOD Evaluate Peak Capacity BAD Calculate Column 2 and Conditions Select Stationary Phases Determine Secondary Oven Offset and Col. 2 Length

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104 Decrease Run Time Optional Shorten column, faster, less peak capacity Ramp faster, less peak capacity Use narrower ID, similar peak capacity, faster

105 Decrease Run Time 90.3 min 63.5 min 60x0.25x0.25/0.6x0.25x /min 40x0.15x0.15/0.3x0.15x /min

106 Decrease Run Time Benzo[b]fluoranthene/Benzo[k]fluoranthene 60x0.25x0.25/0.6x0.25x /min 40x0.15x0.15/0.3x0.15x /min

107 Diesel on 5 x 17 Column Set, +12 C

108 Diesel on 5 x 17 Column Set, +12 C

109 Summary Simply GCxGC tool guides you through the method development process Calculates column dimensions and conditions based on user selected primary column Guides user in selecting stationary phases Guides user in determining the secondary oven temperature offset and secondary column length Guides the user in evaluating stationary phases Guides the user in evaluating peak capacity Guides the user in selected ways to increase peak capacity or decrease run time More than a guide, also a learning tool!

110 For More Information Contact LECO at: World Headquarters/United States In United States: or Outside U.S.A.: See Simply GCxGC at