Slide 1: Chromatography in the Fast Lane
Chromatography in the Fast Lane Fast GC Mark Sinnott Application Engineer December 13, 2018 1
Slide 2: Questions to Ask
Questions to Ask What information do you need from your analysis? Do you have more baseline than you need between your peaks? Do you need to resolve all of the components? Page 2
Slide 3: Variables for Shortening Run Times
Variables for Shortening Run Times •Stationary Phase •Temperature Programming •Carrier Gas: type and linear velocity •Shorten Column Length •Decrease Film Thickness •Decrease Internal Diameter Page 3
Slide 4: Resolution
Resolution N k − 1 Rs = 4 k + 1 Factors effecting Rs Variables Efficiency N = (gas, L, rc) L Length rc radius Retention k = (T, df, rc) df film thickness Selectivity = (T, phase) T Temperature Page 4
Slide 5: Resolution
Resolution N k − 1 Rs = 4 k + 1 Factors effecting Rs Variables Efficiency N = (gas, L, rc) L Length rc radius Retention k = (T, df, rc) df film thickness Selectivity = (T, phase) T Temperature Page 5
Slide 6: Stationary Phase - Common Types
Stationary Phase - Common Types Siloxane polymers Poly(ethylene) glycols Porous polymers Page 6
Slide 7: Selectivity
Selectivity Relative spacing of the chromatographic peaks The result of all non-polar, polarizable and polar interactions that cause a stationary phase to be more or less retentive to one analyte than another Page 7
Slide 8: Optimizing Selectivity
Optimizing Selectivity Match analyte polarity to stationary phase polarity -like dissolves like(oil and water don’t mix) Take advantage of unique interactions between analyte and stationary phase functional groups Page 8
Slide 9: Start with the Right Phase
Start with the Right Phase DB-1 15m x 0.32mm, 0.25µm Oven: 40°C for 2 min 40-120°C at 5°C/min 0 2 4 6 8 10 12 14 Time (min.) DB-Wax 15m, 0.32mm, 0.25µm Oven: 80-190°C at 20°C/min 0 1 2 3 4 5 Time (min.) Page 9
Slide 10: Resolution
Resolution N k − 1 Rs = 4 k + 1 Factors effecting Rs Variables Efficiency N = (gas, L, rc) L Length rc radius Retention k = (T, df, rc) df film thickness Selectivity = (T, phase) T Temperature Page 10
Slide 11: Column Length and Efficiency (Theoretical Plates)
Column Length and Efficiency (Theoretical Plates) Length (m) n 15 69,450 30 138,900 60 277,800 0.25 mm ID n/m = 4630 (for k = 5) Page 11
Slide 12: Column Length and Resolution
Column Length and Resolution R n L Length X 4 = Resolution X 2 t L Page 12
Slide 13: Column Length VS Resolution and Retention: Isothermal
Column Length VS Resolution and Retention: Isothermal R=0.84 R=1.16 R=1.68 2.29 min 4.82 min 8.73 min 15 m 30 m 60 m Double the plates, double the time but not double the the resolution Page 13
Slide 14: Decrease the Length
DECREASE THE LENGTH DB-5 1 4 30 m 2 0.53 mm I.D., 0.5 µm 3 5 0.50 1.00 1.50 2.00 2.50 3.00 3.50 4.00 4.50 5.00 5.50 6.00 6.50 7.00 7.50 8.00 8.50 9.00 .5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0 DB-5 1. Benzene 15 m 2. Toluene 0.53 mm I.D., 0.5 µm 3. Ethylbenzene 4 4. m,p-
Slide 15: Column Length and Cost
Column Length and Cost 15m 30m 60m $$$$ Page 15
Slide 16: Length Summary
Length Summary If you Decrease Length: Efficiency Decrease Resolution Decrease Analysis Time Decrease Pressure Decrease Cost Decrease Page 16
Slide 17: Resolution
Resolution N k − 1 Rs = 4 k + 1 Factors effecting Rs Variables Efficiency N = (gas, L, rc) L Length rc radius Retention k = (T, df, rc) df film thickness Selectivity = (T, phase) T Temperature Page 17
Slide 18: Column Diameter - Theoretical Efficiency
Column Diameter - Theoretical Efficiency Total Plates I.D. (mm) n/m 5m N ~ 112,000 0.05 23,160 10 m N ~ 112,000 0.10 11,580 0.18 6,660 20 m N ~ 112,000 0.20 5830 0.25 4630 30 m N ~ 112,000 0.32 3660 0.45 2840 0.53 2060 k=5 Page 18
Slide 19: Different Column I. D.
Different Column I. D. Equal Phase Ratios Column : DB-624 30 m, 0.53 mm, 3 m Carrier: Helium, 40(cm/sec) Oven: 65°C Injection: Split Detector: FID Column : DB-624 30 m, 0.32 mm, 1.8 m 0 5 10 15 20 Time (min) Page 19
Slide 20: Phase Ratio
PHASE RATIO () Film Thickness Column Dimensions Phase Ratio β 30 m x .53 mm x 3.0 m 44 30 m x .32 mm x 1.8 m 44 KC = k β β = r 2df Page 20
Slide 21: Column Diameter and Capacity
Column Diameter and Capacity I.D. (mm) Capacity (ng) 0.05 1-2 0.10 6-13 0.18 25-55 0.20 35-70 Like Polarity Phase/Solute 0.25 80-160 0.25 µm film thickness 0.32 110-220 0.45 600-800 0.53 1000-2000 Page 21
Slide 22: Column Diameter - Inlet Head Pressures (Helium)
Column Diameter - Inlet Head Pressures (Helium) I.D (mm) Pressure (psig) 0.05 275-400 0.10 90-130 0.18 30-45 0.20 25-40 0.25 15-25 30 meters 0.32 10-20 Hydrogen pressures x 1/2 0.45 3-7 0.53 2-4 Page 22
Slide 23: Column Diameter and Carrier Gas Flow
Column Diameter and Carrier Gas Flow Lower flow rates: Smaller diameter columns Higher flow rates: Larger diameter columns Low flow rates : GC/MS High flow rates: Headspace, purge & trap Page 23
Slide 24: Diameter Summary
Diameter Summary If you decrease the inside diameter: Efficiency Increase Resolution Increase Pressure Increase Capacity Decrease Flow rate Decrease Page 24
Slide 25: Combining a Change in Length with a Change in Diameter
Combining a change in Length with a change in Diameter Decrease Length Decrease Diameter Efficiency Analysis Time Page 25
Slide 26: Carrier Gas Considerations
Carrier Gas Considerations Best velocity? Optimal range of velocities Too low or high results in loss of resolution Balance resolution and analysis time BUT... there is no LAW against going FASTER Page 26
Slide 27: Carrier Gas Considerations: Van Deemter Curve
Carrier Gas Considerations Van Deemter Curve N2 Excessive Diffusion 1.00 Poor Mass Transfer 0.75 H (min) 0.50 He H2 0.25 uopt 60 10 20 30 40 50 60 u (cm/sec) Page 27
Slide 28: Utilizing Computer Controlled Flow Ramping (EPC)
Carrier Gas Considerations Utilizing Computer Controlled Flow Ramping (EPC) Lonely Late Eluters? = P Decrease retention and overall run time by increasing pressure (speed up the gas!) Page 28
Slide 29: Fast Detector Electronics – 6890 FID
Fast Detector Electronics – 6890 FID 200 Hz 100 Hz 50 Hz 20 Hz 10 Hz Proper peak quantitation typically requires a minimum of 10 data points per peak 10 Hz data rate: (peaks less than one second wide will have less than 10 data points) 200 Hz data rate: (peaks as narrow as 50 msec can be handled rel
Slide 30: Easy Options with Method Translation Software
Easy Options with Method Translation Software Different Column Dimensions Switch He to H2 Carrier Gas and Try Faster Velocities Same Column & Gas Type but Faster Velocities Combination of all of the above Page 30
Slide 31: Temperature Programming
Temperature Programming 30m, 0.25mm ID Temperature 10m, 0.1mm ID Temperature Temperature program must be modified to give same temperature of elution (i.e. faster ramps, shorter hold times)
Slide 32: CLP-Pesticides - Original Improved Method
CLP-Pesticides - Original “Improved” Method 0.32mm I.D., Helium Carrier Gas Column: DB-XLB 5,6 30m x 0.32mm i.d., 0.25µm G C 3 - 6 7 0 7 . D \ E C Carrier: D 2 B He, constant flow, 38 cm/s at 120°C 2 Injector: Pulsed Splittless, 220 °C 3 Pulse pressure & time: 35psi for 1.15min 2µL, 50ppb Oven: 120°
Slide 33: Input Original Method Parameters
Input Original Method Parameters Page 33
Slide 34: Same Column and Gas Type Fast Analysis (OPGV)
Same Column and Gas Type Fast Analysis (OPGV) Transfer same dimensions New Velocity New Temp. Program Page 34
Slide 35: Same Column and Gas Type Fast Analysis (OPGV)
1 . 9 e + 0 8 1 . 8 e + 0 8 1 . 7 e + 0 8 Same Column and Gas Type Before 1 . 6 e + 0 8 1 . 5 e + 0 8 1 . 4 e + 0 8 Fast Analysis (OPGV) 1 . 3 e + 0 8 1 . 2 e + 0 8 1 . 1 e + 0 8 1 e + 0 8 9 e + 0 7 8 e + 0 7 7 e + 0 7 6 e + 0 7 5 e + 0 7 4 e + 0 7 3 e + 0 7 No Real 2 e + 0 7 1 e + 0 7 T i m e Chang
Slide 36: Same Column, Hydrogen Carrier Gas Translate Only
Same Column, Hydrogen Carrier Gas Translate Only Page 38
Slide 37: Same Column, H2 Carrier Gas Translate Only
1 . 9 e + 0 8 1 . 8 e + 0 8 1 . 7 e + 0 8 Same Column, H2 Carrier Gas Before 1 . 6 e + 0 8 1 . 5 e + 0 8 1 . 4 e + 0 8 Translate Only 1 . 3 e + 0 8 1 . 2 e + 0 8 1 . 1 e + 0 8 1 e + 0 8 9 e + 0 7 8 e + 0 7 7 e + 0 7 6 e + 0 7 5 e + 0 7 4 e + 0 7 3 e + 0 7 2 e + 0 7 1 e + No Real 0 7 2 . 0 0 4 . 0 0
Slide 38: New Column Dimensions, H2 Gas, Translate Only
New Column Dimensions, H2 Gas, Translate Only Input NEW dimensions Close enough (got lucky) New Velocity New Temp. Program Page 42
Slide 39: New Column Dimensions, H2 Gas, Translate Only
New Column Dimensions, H2 Gas, Translate Only Page 43
Slide 40: New Column Dimensions, H2 Gas, Translate Only
New Column Dimensions, H2 Gas, Translate Only 5 10 11 6 Page 44
Slide 41: New Column Dimensions, H2 Gas, Fast Analysis
New Column Dimensions, H2 Gas, Fast Analysis New Velocity New Temp. Program Page 45
Slide 42: New Column Dimensions, H2 Gas, Fast Analysis
New Column Dimensions, H2 Gas, Fast Analysis G C 8 - 3 3 4 5 . D \ E C D 2 B Better Resolution and Faster Analysis! 2 . 0 0 2 . 5 0 3 . 0 0 3 . 5 0 4 . 0 0 4 . 5 0 5 . 0 0 5 . 5 0 6 . 0 0 6 . 5 0 7 . 0 0 7 . 5 0 Page 46
Slide 43: New Column Dimensions, H2 Gas, Higher Velocities
New Column Dimensions, H2 Gas, Higher Velocities Page 47
Slide 44: New Column Dimensions, H2 Gas, Higher Velocities
New Column Dimensions, H2 Gas, Higher Velocities 105 cm/sec ? 5.5 minutes! 95 cm/sec <6 minutes 85 cm/sec Page 48
Slide 45: Final Method Used at EPA
Column: DB-XLB Final Method Used at EPA Carrier: 20m x 0.18mm i.d., 0.18µm H2, constant flow, 77.3cm/s at 120°C Injector: Pulsed Splittless, 220 °C Pulse pressure & time: 35psi for 0.5min Flow ramp at 6.25min of 99mL/min2 to 3mL/min 2- 3 2mm i.d. liner G C 8 3 6 7 . D \ E C D 2 B 0.5µL, 50ppb Oven:
Slide 46: Final Method Used at EPA
Final Method 2 Used at EPA G C 8 - 3 3 6 7 . D \ E C D 2 B 5 3 7 12 10 DB-XLB 1 8 9 13 11 21 6 19 22 14 15 16 18 4 17 20 G C 8 - 3 3 6 7 . D \ E C D 1 A 1 . 5 0 2 . 0 0 2 . 5 0 3 . 0 0 3 . 5 0 4 . 0 0 4 . 5 0 5 . 0 0 5 . 5 0 6 . 0 0 6 . 5 0 7 . 0 0 2 3 5 7 V 9 10 12 i e w M o d e : I n t e g r a 21
Slide 47: Food/Fragrance – Method translation
Food/Fragrance – Method translation Page 51
Slide 48: Food/Fragrance – Method translation
Food/Fragrance – Method translation Page 52
Slide 49: Spearmint Oil
Spearmint Oil 10.6 min Δ -16.8 min (0.18 mm, H2 Carrier) 17.7 min Δ -9.7 min (0.18 mm, He Carrier) (0.25 mm, He Carrier) 27.4 min 3 8 13 18 23 28 Time (min) Page 53
Slide 50: Spearmint Oil – Resolution Check
Spearmint Oil – Resolution Check Δ -16.8 min (0.18 mm, H2 Carrier) 10.6 min Δ -9.7 min (0.18 mm, He carrier) 17.7 min (0.25 mm, He Carrier) 27.4 min 3 8 13 18 23 28 Page 54
Slide 51: Resolution Maintained
Resolution Maintained Compound Resolution Compounds 0.25 mm 0.18 mm 0.18 mm Helium Helium Hydrogen Sabinene 1.52 1.59 1.56 β-Pinene α-Terpinene 1.61 1.73 1.86 p-Cymene Speed Gain N/A 35% 61% Practical Fast GC Applications with Capillary GC Columns May 19, 2009 Page 55
Slide 52: Conclusions
CONCLUSIONS Stationary Phases – Chosen for optimized selectivity Diameter – Smaller allows shorter length but has less capacity Make Small Changes – Again think capacity Carrier Gas – Hydrogen, high velocity, but can still go fast with He Temperature Program – Scale properly to preserve elution patt
Slide 53: The New Agilent Intuvo 9000 GC System
The New Agilent Intuvo 9000 GC System
Slide 54: Common frustrations with GC
Common frustrations with GC • Measuring column length correctly • Cutting your column correctly • How tight it too tight? • Clipping columns to deal with active sites, then updating retention times
Slide 55: Intuvo…
Common Care and Maintenance Scheme for GC Columns 1. Cut off 6”-1ft of the inlet end of the column. 2. Bake out the column for no more than 2 hours. 3. Cut off more column. (repeat as necessary) Intuvo… Change the guard chip Guard Column
Slide 56: Innovating the GC Flow Path
Innovating the GC Flow Path Conventional Intuvo flow path flow path Click-and-run Inlet Inlet direct connections Guard chip Gold seal Flow chip Nuts and ferrules To detector Classic capillary Intuvo planar column column To detector
Slide 57: Easier and faster maintenance with Intuvo
Easier and faster maintenance with Intuvo • No more ferrules • Direct face seal connections • Audible and tactile click lets you know connection is made • Less unplanned downtime • Fewer batch reruns and precious samples lost
Slide 58: No More - measuring - over-tightening
No More - measuring - over-tightening - trimming
Slide 59: A New Portfolio of GC Consumables
A New Portfolio of GC Consumables UI Inlet Liners Guard Chip Smart Keys Intuvo Flow Chips No-trim column Tools & Accessories
Slide 60: No More: - Measuring - Over-tightening
No More: - Measuring - Over-tightening - Trimming
Slide 61: Tips to Assure a Good Column Installation
Tips to Assure a Good Column Installation 1. Finger tighten until only 1 thread on each of the two nuts is showing. If more than 1 thread is showing, wiggle or re-position the column into place to further finger tighten the nuts to 1 thread.
Slide 62: Tips to Assure a Good Column Installation
Tips to Assure a Good Column Installation 2. Check that the small integrated column nuts on the column are in form fitted place on the heater in the instrument. 3. Click and Run!!
Slide 63: Smart Key Technology
Smart Key Technology • Smart chip tells your Intuvo what you have • Sets temperature limits for you • Keep track of performance with read/writeable Smart Key
Slide 64: Where Does it Get Dirty?
Where Does it Get Dirty? Here Here Here Here Here Here Not the Column! Page 78
Slide 65: New Autonomous Leak Checking
New Autonomous Leak Checking