Staying Connected in GC Daron Decker / Eric Pavlich Chromatography Technical Specialists Page 1
Leaks (Oxygen) Damages GC Columns Repair of the GC column is impossible Replacements means re-calibration Replacement means delay Replacement column costs money Solution = No Leaks! Page 2
Installing a GC Column Can Be Challenging A routine, basic procedure but not easy to do Plus a minimum of 2 chances to get it wrong! Very small parts Wrenches in cramped, dark space Even when done correctly, fittings can still leak (shrinking ferrule syndrome) Page 3
Ferrules Graphite/Polyimide Graphite Flexible Metal 350 C Limited re-use Shrinks in temp cycles Needs retightening Prone to leaks Inlets MS, ECD 450 C Limited re-use Permeable Contamination Flaking Inlets FID, NPD HT Applications 450 C No re-use No damaged surfaces Pricy CFT devices Backflush
What if you Could install the column easily Finger tighten, without tools that cause over tightening And make leak free connections Which don t need to be retightened Every time? Page 5
Self-Tightening Column Nuts Innovative spring-driven piston continuously presses against ferrule Less wasted time: No retightening needed after repeated thermal cycles Ease of use: Finger-tight, consistent connections without tools Leak Free = Lower column bleed: Longer column life Video at agilent.com/chem/stnutvideo Page 6
Self Tightening Column Nuts For inlet or detector p/n 5190-6194 For mass spec transfer line p/n 5190-5233 Page 7
Solving Shrinking Ferrule Syndrome Page 8
What to Use When? Application Requirement Ease of Use - finger tighten / no wrench Inertness for active analytes Installed or used hardware Self Tightening Column nut with short Graphite/Polyimide blend ferrule x x UltiMetal Plus Flexible Metal ferrule Same style ferrule at inlet and MS interface x High temp above 350 x Mass Spec Interface fitting x Capillary Flow Technology device x Pre-swage for precise height into fitting x x Re-use of ferrule x x
Ferrule Pre-swaging Tools Ensures proper length of column into the fittings, every time For graphite or metal ferrules Metal ferrule tool Graphite ferrule tool G3440-80218 G3440-80217 Page 10
Newest Pre-swaging Tool Coming Soon for CFT Devices! Page 11
Other Connections in GC Guard Columns, Pre-Columns Capillary Flow Technology - Backflushing - Multiple Columns/Detectors - Deans Switch Page 12
Splitless Injection Reverse Solvent Effect Hexane 5 6 Methanol 4 1 4 2 5 6 2 3 1 3 0 1 2 3 4 5 6 Time (min.) 1 2 3 4 5 6 Time (min.) DB-1, 15 m x 0.25 mm I.D., 0.25 µm 50 C for 1 min, 50-210 C at 20 /min; Helium at 30 cm/sec 1. 1,3-DCP 2. 3-hexanol 3. butyl acetate 4. 1-heptanol 5. 3-octanone 6. 1,2-dichlorobenzene Page 13
Retention Gap Also Called A Guard Column Injector Detector Deactivated Fused Silica Tubing Union Column Usually 2-10 meters long and same diameter as the column (or larger if needed) Page 14
Fixing the Reverse Solvent Effect 3 m x 0.25 mm I.D. Retention Gap Hexane 1 Methanol 4 5 6 2 3 4 1 2 3 5 6 0 1 2 3 4 5 6 Time (min.) 1 2 3 4 5 6 Time (min.) DB-1, 15 m x 0.25 mm I.D., 0.25 µm 50 C for 1 min, 50-210 C at 20 /min; Helium at 30 cm/sec 1. 1,3-DCP 2. 3-hexanol 3. butyl acetate 4. 1-heptanol 5. 3-octanone 6. 1,2-dichlorobenzene Page 15
Press Fit Connectors Competitor Press-Tight Agilent Ultra Inert Press Fit Inertness, seal and transparency are key parameters Page 16
Pull Test Machine: ASTM Test Used in Packaging Page 17
Column - press-fit connector pull test Page 18
Maximum Force Required to pull apart 2.5 Pull Value, 0.25 mm I.D. Columns Pounds (force) 2.0 1.5 1.0 Strong bond between FS polyimide & press fit UI deactivation layer 0.5 0.0 1 2 3 4 Ultra Inert Quartz Fused Silica Glass Press Fit Connector Type Page 19
1.4E+00 Pull Value, 0.53 mm ID Columns 1.2E+00 1.0E+00 Bond strength also dependent on contact angle and contact surface area Between polyimide and press-fit 8.0E-01 6.0E-01 4.0E-01 2.0E-01 0.0E+00 1 2 3 UI Qtz FS Page 20
Ultimate Union and Retention Gap (Preferred by Many) Page 21
Two Connection Options from Agilent Ultra Inert Press Fit Connectors Capillary Flow Technology Page 22
Purged Capillary Flow Devices 2-Way Splitter with Makeup 3-Way Splitter with Makeup Deans Switch Purged Union (most recent) All Purged Capillary Flow Devices are Capable of Backflushing Page 23
Backflush with Purged Union or Any Purged Capillary Flow Technology Device Split Vent Trap During GC Run Aux EPC 4 psi Inlet MSD 25 psi Split Vent Trap Column After GC Run Purged CFT Device Aux EPC 80 psi Inlet MSD 1 psi Column Purged CFT Device performance turbo recommended Page 24
Milk Extract It took additional 33 mins and column to 320 o C to remove these high boilers. Run stopped at 42 min and backflushed at 280 o C for 7 mins. Blank run after backflushing showing the column was clean. 5 10 15 20 25 30 35 40 45 50 55 60 65 70 min Page 25
Post-Column Backflush Injector Detector Transfer Line Column Purged Ultimate Union
Mid-Column Backflush Injector Detector Column Front Half Back Half Purged Ultimate Union
Pre-Column Backflush Injector Detector Pre-Column Column Purged Ultimate Union
Without Backflush: A Serious Problem Abundance 4.6e+07 4.4e+07 4.2e+07 4e+07 3.8e+07 3.6e+07 3.4e+07 3.2e+07 3e+07 2.8e+07 2.6e+07 2.4e+07 2.2e+07 2e+07 1.8e+07 1.6e+07 1.4e+07 1.2e+07 1e+07 8000000 6000000 4000000 2000000 0 Time A: TIC: lettuce_blank.d\data.ms B: TIC: lettuce_blank3.d\data.ms Data provided by MSD user in Almeria, Spain After only 3 10-µL injections, the background is significantly higher (increase chemical noise is every spectrum) 4.00 6.00 8.00 10.00 12.00 14.00 16.00 18.00 20.00 B A Overlay of two chromatograms of a blank extract injected BEFORE (A) and AFTER (B) three injections without backflush Page 29
With Backflush: No Increased Background (Less Spectral Noise) and Consistent Retention Times Abundance 4.6e+07 4.4e+07 4.2e+07 4e+07 3.8e+07 3.6e+07 3.4e+07 3.2e+07 3e+07 2.8e+07 2.6e+07 2.4e+07 2.2e+07 2e+07 1.8e+07 1.6e+07 1.4e+07 1.2e+07 1e+07 8000000 6000000 4000000 2000000 0 Time TIC: lettuce_10_ppb.d\data.ms TIC: lettuce_100_ppb.d\data.ms TIC: lettuce_5_ppb.d\data.ms Data provided by user in Almeria, Spain Stable retention times and baseline... less chemical noise 4.00 6.00 8.00 10.00 12.00 14.00 16.00 18.00 20.00 Overlay of three chromatograms of lettuce extract run with 2 min of back flush Page 30
Conclusions Never have a leak (no oxygen) Self-Tightening Nuts - solves shrinking ferrule syndrome. Ultra Inert Press Fit Connectors the most cost effective and more reliable than previous press tight connectors. CFT and Ulti-Metal FMF - the most reliable, but pricey. Guard columns, pre-columns, multiple columns/detectors, and backflushing all now possible with reliable, leak-free connections. Page 31
Agilent Better GC Connections www.agilent.com/chem/bettergcconnections Order the poster View the video