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- Heaters/Source
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- Agilent Heaters and SensorsMass Spectrometry, Scientific Supplies & ManufacturingScientific Instrument Services 5973 Source Heater Tamper Resistant Allen Wrench 5973/5975 Quad Sensor 5985 Source Heater Assembly Agilent Interface Heater Assembly 5971 Interface Heater
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- Reference Material on InstrumentationArticle - A High Temperature Direct Probe for a Mass Spectrometer Design of a Direct Exposure Probe and Controller for use ona Hewlett-Packard 5989 Mass Spectrometer SIS AP1000 AutoProbe™ SIS AP2000 AutoProbe™ - Description of System HPP7: Direct Probe Electronics Console HPP7: Direct Probe for the Agilent (HP) 5973/5975 MSD HPP7: HP Direct Probe Application Notes HPP7: Installation Directions for the Direct Probe HPP7: Side Cover for the HP 5973 MSD HPP7: Support HPP7: Probe Inlet System for the Agilent (HP) 5973 and 5975 MSD with Automatic Indexed Stops HPP7: Theory of Operation of the Direct Probe and Probe Inlet System Direct Thermal Extraction Thermal Desorption Application Notes Environmental Thermal Desorption Application Notes Food Science Thermal Desorption Application Notes Forensic Thermal Desorption Application Notes GC Cryo-Trap Application Notes Headspace Application Notes Purge & Trap Thermal Desorption Application Notes Theory of Operation of the AutoDesorb® System AutoDesorb Notes for SIS Dealers Adsorbent Resin Application Notes Installation of the Short Path Thermal Desorption System on Agilent (HP) and Other GCs Installation of the Short Path Thermal Desorption System on a Varian 3400 GC AutoDesorb® System Development Team Thermal Desorption Applications and Reference Materials Installation of the Short Path Thermal Desorption System - TD5 Part I - Design & Operation of the Short Path ThermalDesorption System Installation Instructions for the Model 951 GC Cryo-Trap on the HP 5890 Series GC Installation Instructions for the Model 961 GC Cryo-Trap on the HP 5890 Series GC Operation of the Model 951/961 GC Cryo-Trap SIS GC Cryo Traps - Theory of Operation NIST/EPA/NIH Mass Spectral Enhancements - 1998 version (NIST98) SIMION 3D Ion Optics Class Mass Spectrometer Source Cleaning Methods MS Tip: Mass Spectrometer Source Cleaning Procedures Mass Spec Source Cleaning Procedures Micro-Mesh® Abrasive Sheets Research Papers Using New Era Syringe Pump Systems EI Positive Ion Spectra for Perfluorokerosene (PFK) Cap Liner Information How do I convert between fluid oz and milliliters? Which bottle material should I choose? Which bottle mouth should I choose? The Bottle Selection Guide CGA Connections for Gas Tanks Chemical Reaction Interface Mass Spectrometry (CRIMS)
- Instrument Tubing
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- Gas RegulatorsModel 3530 Series - Single Stage Purity Brass Regulator Model 3510 Series - Single Stage High Purity Stainless Steel Regulators Model 3120 Series - Dual Stage Purity Brass Regulator Model 3810 Series - Dual Stage High Purity Stainless Steel Regulators Tescom Gas Line Regulators 3420 Series Tescom Gas Line Regulators 3450 Series Concoa In-Line Regulators Model 304 Series Concoa In-Line Regulators Model 324 Series
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- GCColumns Fused Silica Tubing Instrument Tubing Injection Port Liners Septa by Manufacturer SIS GC Cryo-Traps Ferrules Valves Swagelok® Fittings Pyrolysis Probe Accessories Gas Generators Gas Regulators Gas Purifiers and Filters Syringes SGE MEPS™-Micro Extraction by Packed Sorbent Purge and Trap System SGE SilFlow™ Stainless Steel Micro-Fluidic Platform Accessories NIST GC RI Library Other GC Supplies Catalog Page D1
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- GC Cryo-traps
- LiteratureApplication Notes Adsorbent Resins Guide Mass Spec Tips SDS Sheets FAQ MS Calibration Compound Spectra Manuals MS Links/Labs/ Organizations MS Online Tools Flyers on Products/Services Scientific Supplies Catalog About Us NextAdvance Bullet Blender® Homogenizer Protocols Micro-Mesh® Literature Instrumentation Literature Agilent GC/MS Literature SIS News / E-Mail Newsletter NIST MS Database - Update Notifications
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- Purge & Trap Thermal Desorption Application NotesNote 97: Flavor Profiles of Imported and Domestic Beers by Purge & Trap Thermal Desorption GC/MS Note 93: Detection of Benzene in Carbonated Beverages with Purge & Trap Thermal Desorption GC/MS Note 43: Volatile Organic Composition In Blueberries Note 42: The Influence of Pump Oil Purity on Roughing Pumps Note 38: A New Micro Cryo-Trap For Trapping Of Volatiles At the Front Of a GC Capillary Column Note 35: Volatile Organics Composition of Cranberries Note 34: Selection Of Thermal Desorption and Cryo-Trap Parameters In the Analysis Of Teas Note 33: Changes in Volatile Organic Composition in Milk Over Time Note 32: Selection and Use of Adsorbent Resins for Purge and Trap Thermal Desorption Applications Note 31: Volatile Organic Composition in Several Cultivars of Peaches Note 30: Comparison Of Cooking Oils By Direct Thermal Extraction and Purge and Trap GC/MS Note 26: Volatile Organics Present in Recycled Air Aboard a Commercial Airliner Note 25: Flavor and Aroma in Natural Bee Honey Note 23: Frangrance Qualities in Colognes Note 22: Comparison Of Volatile Compounds In Latex Paints Note 21: Detection and Identification Of Volatile and Semi-Volatile Organics In Synthetic Polymers Used In Food and Pharmaceutical Packaging Note 20: Using Direct Thermal Desorption to Assess the Potential Pool of Styrene and 4-Phenylcyclohexene In Latex-Backed Carpets Note 18: Determination of Volatile Organic Compounds In Mushrooms Note 17: Identification of Volatile Organics in Wines Over Time Note 16: Analysis of Indoor Air and Sources of Indoor Air Contamination by Thermal Desorption Note 14: Identification of Volatiles and Semi-Volatiles In Carbonated Colas Note 8: Detection of Volatile Organic Compounds In Liquids Utilizing the Short Path Thermal Desorption System Note 3: Indoor Air Pollution Note 2: Detection of Arson Accelerants Using Dynamic Headspace with Tenax® Cartridges Thermal Desorption and Cryofocusing
- GC Cryo-Trap Application NotesNote 43: Volatile Organic Composition In Blueberries Note 42: The Influence of Pump Oil Purity on Roughing Pumps Note 41: Hydrocarbon Production in Pine by Direct Thermal Extraction Note 40: Comparison of Septa by Direct Thermal Extraction Note 39: Comparison of Sensitivity Of Headspace GC, Purge and Trap Thermal Desorption and Direct Thermal Extraction Techniques For Volatile Organics Note 38: A New Micro Cryo-Trap For Trapping Of Volatiles At the Front Of a GC Capillary Column Note 37: Volatile Organic Emissions from Automobile Tires Note 36: Identification Of Volatile Organic Compounds In a New Automobile Note 34: Selection Of Thermal Desorption and Cryo-Trap Parameters In the Analysis Of Teas Note 31: Volatile Organic Composition in Several Cultivars of Peaches Note 30: Comparison Of Cooking Oils By Direct Thermal Extraction and Purge and Trap GC/MS Note 29: Analysis Of Volatile Organics In Oil Base Paints By Automated Headspace Sampling and GC Cryo-Focusing Note 28: Analysis Of Volatile Organics In Latex Paints By Automated Headspace Sampling and GC Cryo-Focusing Note 27: Analysis of Volatile Organics In Soils By Automated Headspace GC Note 24: Selection of GC Guard Columns For Use With the GC Cryo-Trap Note 19: A New Programmable Cryo-Cooling/Heating Trap for the Cryo-Focusing of Volatiles and Semi-Volatiles at the Head of GC Capillary Columns
- Food Science Thermal Desorption Application NotesNote 102: Identification of Contaminants in Powdered Beverages by Direct Extraction Thermal Desorption GC/MS Note 101: Identification of Contaminants in Powdered Foods by Direct Extraction Thermal Desorption GC/MS Note 98: Flavor and Aroma Profiles of Truffle Oils by Thermal Desorption GC/MS Note 93: Detection of Benzene in Carbonated Beverages with Purge & Trap Thermal Desorption GC/MS Note 43: Volatile Organic Composition In Blueberries Note 41: Hydrocarbon Production in Pine by Direct Thermal Extraction Note 35: Volatile Organics Composition of Cranberries Note 33: Changes in Volatile Organic Composition in Milk Over Time Note 31: Volatile Organic Composition in Several Cultivars of Peaches Note 30: Comparison Of Cooking Oils By Direct Thermal Extraction and Purge and Trap GC/MS Note 25: Flavor and Aroma in Natural Bee Honey Note 21: Detection and Identification Of Volatile and Semi-Volatile Organics In Synthetic Polymers Used In Food and Pharmaceutical Packaging Note 18: Determination of Volatile Organic Compounds In Mushrooms Note 17: Identification of Volatile Organics in Wines Over Time Note 14: Identification of Volatiles and Semi-Volatiles In Carbonated Colas Note 12: Identification of the Volatile and Semi-Volatile Organics In Chewing Gums By Direct Thermal Desorption Note 11: Flavor/Fragrance Profiles of Instant and Ground Coffees By Short Path Thermal Desorption Note 9: Methodologies For the Quantification Of Purge and Trap Thermal Desorption and Direct Thermal Desorption Analyses Note 8: Detection of Volatile Organic Compounds In Liquids Utilizing the Short Path Thermal Desorption System Note 6: Direct Thermal Analysis of Plastic Food Wraps Using the Short Path Thermal Desorption System Note 5: Direct Thermal Analysis Using the Short Path Thermal Desorption System Note 4: Direct Analysis of Spices and Coffee Note 1: Determination of Off-Odors and Other Volatile Organics In Food Packaging Films By Direct Thermal Analysis-GC-MS
- Direct Thermal Extraction Thermal Desorption Application NotesNote 103: EPA Method 325B, Novel Thermal Desorption Instrument Modification to Improve Sensitivity Note 102: Identification of Contaminants in Powdered Beverages by Direct Extraction Thermal Desorption GC/MS Note 101: Identification of Contaminants in Powdered Foods by Direct Extraction Thermal Desorption GC/MS Note 100: Volatile and Semi-Volatile Profile Comparison of Whole Versus Cracked Versus Dry Homogenized Barley Grains by Direct Thermal Extraction Note 99: Volatile and Semi-Volatile Profile Comparison of Whole vs. Dry Homogenized Wheat, Rye and Barley Grains by Direct Thermal Extraction GC/MS Note 98: Flavor and Aroma Profiles of Truffle Oils by Thermal Desorption GC/MS Note 95: Detection of Explosives on Clothing Material by Direct and AirSampling Thermal Desorption GC/MS Note 94: Detection of Nepetalactone in the Nepeta Cataria Plant by Thermal Desorption GC/MS Note 41: Hydrocarbon Production in Pine by Direct Thermal Extraction Note 40: Comparison of Septa by Direct Thermal Extraction Note 39: Comparison of Sensitivity Of Headspace GC, Purge and Trap Thermal Desorption and Direct Thermal Extraction Techniques For Volatile Organics Note 37: Volatile Organic Emissions from Automobile Tires Note 30: Comparison Of Cooking Oils By Direct Thermal Extraction and Purge and Trap GC/MS Note 21: Detection and Identification Of Volatile and Semi-Volatile Organics In Synthetic Polymers Used In Food and Pharmaceutical Packaging Note 20: Using Direct Thermal Desorption to Assess the Potential Pool of Styrene and 4-Phenylcyclohexene In Latex-Backed Carpets Note 13: Identification and Quantification of Semi-Volatiles In Soil Using Direct Thermal Desorption Note 12: Identification of the Volatile and Semi-Volatile Organics In Chewing Gums By Direct Thermal Desorption Note 11: Flavor/Fragrance Profiles of Instant and Ground Coffees By Short Path Thermal Desorption Note 10: Quantification of Naphthalene In a Contaminated Pharmaceutical Product By Short Path Thermal Desorption Note 9: Methodologies For the Quantification Of Purge and Trap Thermal Desorption and Direct Thermal Desorption Analyses Note 7: Chemical Residue Analysis of Pharmaceuticals Using The Short Path Thermal Desorption System Note 6: Direct Thermal Analysis of Plastic Food Wraps Using the Short Path Thermal Desorption System Note 5: Direct Thermal Analysis Using the Short Path Thermal Desorption System Note 4: Direct Analysis of Spices and Coffee Note 1: Determination of Off-Odors and Other Volatile Organics In Food Packaging Films By Direct Thermal Analysis-GC-MS
- Application NotesNote 103: EPA Method 325B, Novel Thermal Desorption Instrument Modification to Improve Sensitivity Note 102: Identification of Contaminants in Powdered Beverages by Direct Extraction Thermal Desorption GC/MS Note 101: Identification of Contaminants in Powdered Foods by Direct Extraction Thermal Desorption GC/MS Note 100: Volatile and Semi-Volatile Profile Comparison of Whole Versus Cracked Versus Dry Homogenized Barley Grains by Direct Thermal Extraction Note 99: Volatile and Semi-Volatile Profile Comparison of Whole vs. Dry Homogenized Wheat, Rye and Barley Grains by Direct Thermal Extraction GC/MS Note 98: Flavor and Aroma Profiles of Truffle Oils by Thermal Desorption GC/MS Note 97: Flavor Profiles of Imported and Domestic Beers by Purge & Trap Thermal Desorption GC/MS Note 96: Reducing Warping in Mass Spectrometer Filaments, with SISAlloy® Yttria/Rhenium Filaments Note 95: Detection of Explosives on Clothing Material by Direct and AirSampling Thermal Desorption GC/MS Note 94: Detection of Nepetalactone in the Nepeta Cataria Plant by Thermal Desorption GC/MS Note 93: Detection of Benzene in Carbonated Beverages with Purge & Trap Thermal Desorption GC/MS Note 92: Yttria Coated Mass Spectrometer Filaments Note 91: AutoProbe DEP Probe Tip Temperatures Note 90: An Automated MS Direct Probe for use in an Open Access Environment Note 89: Quantitation of Organics via a Mass Spectrometer Automated Direct Probe Note 88: Analysis of Silicone Contaminants on Electronic Components by Thermal Desorption GC-MS Note 87: Design and Development of an Automated Direct Probe for a Mass Spectrometer Note 86: Simulation of a Unique Cylindrical Quadrupole Mass Analyzer Using SIMION 7.0. Note 85: Replacing an Electron Multiplier in the Agilent (HP) 5973 MSD Note 84: Vacuum Pump Exhaust Filters - Charcoal Exhaust Traps Note 83: Vacuum Pump Exhaust Filters - Oil Mist Eliminators Note 82: Vacuum Pump Exhaust Filters Note 81: Rapid Bacterial Chemotaxonomy By DirectProbe/MSD Note 80: Design, Development and Testing of a Microprocessor ControlledAutomated Short Path Thermal Desorption Apparatus Note 79: Volatile Organic Compounds From Electron Beam Cured and Partially Electron Beam Cured Packaging Using Automated Short Path Thermal Desorption Note 78: A New Solution to Eliminate MS Down-Time With No-Tool-Changing of Analytical GC Columns Note 77: The Determination of Volatile Organic Compounds in VacuumSystem Components Note 76: Determination of the Sensitivity of a CRIMS System Note 75: An Apparatus for Sampling Volatile Organics From LivePlant Material Using Short Path Thermal Desorption Note 74: Examination of Source Design in Electrospray-TOF Using SIMION 3D Note 73: The Analysis of Perfumes and their Effect on Indoor Air Pollution Note 72: 1998 Version of the NIST/EPA/NIH Mass Spectral Library, NIST98 Note 71: Flavor Profile Determination of Rice Samples Using Shor tPath Thermal Desorption GC Methods Note 70: Application of SIMION 6.0 To a Study of the Finkelstein Ion Source: Part II Note 69: Application of SIMION 6.0 To a Study of the Finkelstein Ion Source: Part 1 Note 68: Use of a PC Plug-In UV-Vis Spectrometer To Monitor the Plasma Conditions In GC-CRIMS Note 67: Using Chemical Reaction Interface Mass Spectrometry (CRIMS) To Monitor Bacterial Transport In In Situ Bioremediation Note 66: Probe Tip Design For the Optimization of Direct Insertion Probe Performance Note 65: Determination of Ethylene by Adsorbent Trapping and Thermal Desorption - Gas Chromatography Note 64: Comparison of Various GC/MS Techniques For the Analysis of Black Pepper (Piper Nigrum) Note 63: Determination of Volatile and Semi-Volatile Organics in Printer Toners Using Thermal Desorption GC Techniques Note 62: Analysis of Polymer Samples Using a Direct Insertion Probe and EI Ionization Note 61: Analysis of Sugars Via a New DEP Probe Tip For Use With theDirect Probe On the HP5973 MSD Note 60: Programmable Temperature Ramping of Samples Analyzed ViaDirect Thermal Extraction GC/MS Note 59: Computer Modeling of a TOF Reflectron With Gridless Reflector Using SIMION 3D Note 58: Direct Probe Analysis and Identification of Multicomponent Pharmaceutical Samples via Electron Impact MS Note 57: Aroma Profiles of Lavandula species Note 56: Mass Spec Maintenance & Cleaning Utilizing Micro-Mesh® Abrasive Sheets Note 55: Seasonal Variation in Flower Volatiles Note 54: Identification of Volatile Organic Compounds in Office Products Note 53: SIMION 3D v6.0 Ion Optics Simulation Software Note 52: Computer Modeling of Ion Optics in Time-of-Flight mass Spectrometry Using SIMION 3D Note 51: Development and Characterization of a New Chemical Reaction Interface for the Detection of Nonradioisotopically Labeled Analytes Using Mass Spectrometry (CRIMS) Note 50: The Analysis of Multiple Component Drug Samples Using a Direct Probe Interfaced to the HP 5973 MSD Note 49: Analysis of Cocaine Utilizing a New Direct Insertion Probe on a Hewlett Packard 5973 MSD Note 48: Demonstration of Sensitivity Levels For the Detection of Caffeine Using a New Direct Probe and Inlet for the HP 5973 MSD Note 47: The Application Of SIMION 6.0 To Problems In Time-of-Flight Mass Spectrometry Note 46: Delayed Extraction and Laser Desorption: Time-lag Focusing and Beyond Note 45: Application of SIMION 6.0 to Filament Design for Mass Spectrometer Ionization Sources Note 44: The Design Of a New Direct Probe Inlet For a Mass Spectrometer Note 43: Volatile Organic Composition In Blueberries Note 42: The Influence of Pump Oil Purity on Roughing Pumps Note 41: Hydrocarbon Production in Pine by Direct Thermal Extraction Note 40: Comparison of Septa by Direct Thermal Extraction Note 39: Comparison of Sensitivity Of Headspace GC, Purge and Trap Thermal Desorption and Direct Thermal Extraction Techniques For Volatile Organics Note 38: A New Micro Cryo-Trap For Trapping Of Volatiles At the Front Of a GC Capillary Column Note 37: Volatile Organic Emissions from Automobile Tires Note 36: Identification Of Volatile Organic Compounds In a New Automobile Note 35: Volatile Organics Composition of Cranberries Note 34: Selection Of Thermal Desorption and Cryo-Trap Parameters In the Analysis Of Teas Note 33: Changes in Volatile Organic Composition in Milk Over Time Note 32: Selection and Use of Adsorbent Resins for Purge and Trap Thermal Desorption Applications Note 31: Volatile Organic Composition in Several Cultivars of Peaches Note 30: Comparison Of Cooking Oils By Direct Thermal Extraction and Purge and Trap GC/MS Note 29: Analysis Of Volatile Organics In Oil Base Paints By Automated Headspace Sampling and GC Cryo-Focusing Note 28: Analysis Of Volatile Organics In Latex Paints By Automated Headspace Sampling and GC Cryo-Focusing Note 27: Analysis of Volatile Organics In Soils By Automated Headspace GC Note 26: Volatile Organics Present in Recycled Air Aboard a Commercial Airliner Note 25: Flavor and Aroma in Natural Bee Honey Note 24: Selection of GC Guard Columns For Use With the GC Cryo-Trap Note 23: Frangrance Qualities in Colognes Note 22: Comparison Of Volatile Compounds In Latex Paints Note 21: Detection and Identification Of Volatile and Semi-Volatile Organics In Synthetic Polymers Used In Food and Pharmaceutical Packaging Note 20: Using Direct Thermal Desorption to Assess the Potential Pool of Styrene and 4-Phenylcyclohexene In Latex-Backed Carpets Note 19: A New Programmable Cryo-Cooling/Heating Trap for the Cryo-Focusing of Volatiles and Semi-Volatiles at the Head of GC Capillary Columns Note 18: Determination of Volatile Organic Compounds In Mushrooms Note 17: Identification of Volatile Organics in Wines Over Time Note 16: Analysis of Indoor Air and Sources of Indoor Air Contamination by Thermal Desorption Note 14: Identification of Volatiles and Semi-Volatiles In Carbonated Colas Note 13: Identification and Quantification of Semi-Volatiles In Soil Using Direct Thermal Desorption Note 12: Identification of the Volatile and Semi-Volatile Organics In Chewing Gums By Direct Thermal Desorption Note 11: Flavor/Fragrance Profiles of Instant and Ground Coffees By Short Path Thermal Desorption Note 10: Quantification of Naphthalene In a Contaminated Pharmaceutical Product By Short Path Thermal Desorption Note 9: Methodologies For the Quantification Of Purge and Trap Thermal Desorption and Direct Thermal Desorption Analyses Note 8: Detection of Volatile Organic Compounds In Liquids Utilizing the Short Path Thermal Desorption System Note 7: Chemical Residue Analysis of Pharmaceuticals Using The Short Path Thermal Desorption System Note 6: Direct Thermal Analysis of Plastic Food Wraps Using the Short Path Thermal Desorption System Note 5: Direct Thermal Analysis Using the Short Path Thermal Desorption System Note 4: Direct Analysis of Spices and Coffee Note 3: Indoor Air Pollution Note 2: Detection of Arson Accelerants Using Dynamic Headspace with Tenax® Cartridges Thermal Desorption and Cryofocusing Note 1: Determination of Off-Odors and Other Volatile Organics In Food Packaging Films By Direct Thermal Analysis-GC-MS Tech No. "A" Note 14: Elimination of "Memory" Peaks in Thermal Desorption Improving Sensitivity in the H.P. 5971 MSD and Other Mass Spectrometers - Part I of II Improving Sensitivity in the H.P. 5971 MSD and Other Mass Spectrometers- Part II of II Adsorbent Resins Guide Development and Field Tests of an Automated Pyrolysis Insert for Gas Chromatography. Hydrocarbon Production in Pine by Direct Thermal Extraction A New Micro Cryo-Trap for the Trapping of Volatiles at the Front of a GC Capillary (019P) - Comparison of Septa by Direct Thermal Extraction Volatile Organic Composition in Blueberry Identification of Volatile Organic Compounds in Office Products Detection and Indentification of Volatiles in Oil Base Paintsby Headspace GC with On Column Cryo-Trapping Evaluation of Septa Using a Direct Thermal Extraction Technique INFLUENCE OF STORAGE ON BLUEBERRY VOLATILES Selection of Thermal Desorption and Cryo-Trap Parameters in the Analysis of Teas Redesign and Performance of a Diffusion Based Solvent Removal Interface for LC/MS The Design of a New Direct Probe Inlet for a Mass Spectrometer Analytes Using Mass Spectrometry (CRIMS) Application of SIMION 6.0 to Filament Design for Mass Spectrometer Ionization Sources A Student Guide for SIMION Modeling Software Application of SIMION 6.0 to Problems in Time-of-flight Mass Spectrometry Comparison of Sensitivity of Headspace GC, Purge and TrapThermal Desorption and Direct Thermal Extraction Techniques forVolatile Organics The Influence of Pump Oil Purity on Roughing Pumps Analysis of Motor Oils Using Thermal Desorption-Gas Chromatography-Mass Spectrometry IDENTIFICATION OF VOLATILE ORGANIC COMPOUNDS IN PAPER PRODUCTS Computer Modeling of Ion Optics in Time-of-Flight mass Spectrometry using SIMION 3D Seasonal Variation in Flower Volatiles Development of and Automated Microprocessor Controlled Gas chromatograph Fraction Collector / Olfactometer Delayed Extraction and Laser Desorption: Time-lag Focusing and Beyond A New Micro Cryo-Trap for the Trapping of Volatiles at the Front of a GC Column Design of a Microprocessor Controlled Short Path Thermal Desorption Autosampler Computer Modeling of Ion Optics in Time-of-Flight Mass Spectrometry Using SIMION 3D Thermal Desorption Instrumentation for Characterization of Odors and Flavors
- AccessoriesTD Supply Kit Desorption Tubes Adsorbent Resins Desorption Tube Needles Desorption Tube Seals Desorption System Fittings GC Cryo-Trap Extraction Cell TD Sample Loader Prepacked, Conditioned Desorption Tubes Desorption Tube Packing Accessories Stainless Steel Purge Heads Injection Port Liners Tenax TA Poster TD Application Notes Customer Service
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- Thermal Desorption Applications and Reference MaterialsDirect Thermal Extraction Headspace Environmental Food Science Applications Pharmaceuticals Forensic Note 103: EPA Method 325B, Novel Thermal Desorption Instrument Modification to Improve Sensitivity Note 102: Identification of Contaminants in Powdered Beverages by Direct Extraction Thermal Desorption GC/MS Note 101: Identification of Contaminants in Powdered Foods by Direct Extraction Thermal Desorption GC/MS Note 100: Volatile and Semi-Volatile Profile Comparison of Whole Versus Cracked Versus Dry Homogenized Barley Grains by Direct Thermal Extraction Note 99: Volatile and Semi-Volatile Profile Comparison of Whole vs. Dry Homogenized Wheat, Rye and Barley Grains by Direct Thermal Extraction GC/MS Note 98: Flavor and Aroma Profiles of Truffle Oils by Thermal Desorption GC/MS Note 97: Flavor Profiles of Imported and Domestic Beers by Purge & Trap Thermal Desorption GC/MS Note 95: Detection of Explosives on Clothing Material by Direct and AirSampling Thermal Desorption GC/MS Note 94: Detection of Nepetalactone in the Nepeta Cataria Plant by Thermal Desorption GC/MS Note 93: Detection of Benzene in Carbonated Beverages with Purge & Trap Thermal Desorption GC/MS Note 88: Analysis of Silicone Contaminants on Electronic Components by Thermal Desorption GC-MS Note 84: Vacuum Pump Exhaust Filters - Charcoal Exhaust Traps Note 83: Vacuum Pump Exhaust Filters - Oil Mist Eliminators Note 82: Vacuum Pump Exhaust Filters Note 80: Design, Development and Testing of a Microprocessor ControlledAutomated Short Path Thermal Desorption Apparatus Note 79: Volatile Organic Compounds From Electron Beam Cured and Partially Electron Beam Cured Packaging Using Automated Short Path Thermal Desorption Note 77: The Determination of Volatile Organic Compounds in VacuumSystem Components Note 75: An Apparatus for Sampling Volatile Organics From LivePlant Material Using Short Path Thermal Desorption Note 73: The Analysis of Perfumes and their Effect on Indoor Air Pollution Note 71: Flavor Profile Determination of Rice Samples Using Shor tPath Thermal Desorption GC Methods Note 65: Determination of Ethylene by Adsorbent Trapping and Thermal Desorption - Gas Chromatography Note 64: Comparison of Various GC/MS Techniques For the Analysis of Black Pepper (Piper Nigrum) Note 63: Determination of Volatile and Semi-Volatile Organics in Printer Toners Using Thermal Desorption GC Techniques Note 60: Programmable Temperature Ramping of Samples Analyzed ViaDirect Thermal Extraction GC/MS Note 57: Aroma Profiles of Lavandula species Note 55: Seasonal Variation in Flower Volatiles Note 54: Identification of Volatile Organic Compounds in Office Products Note 43: Volatile Organic Composition In Blueberries Note 42: The Influence of Pump Oil Purity on Roughing Pumps Note 41: Hydrocarbon Production in Pine by Direct Thermal Extraction Note 40: Comparison of Septa by Direct Thermal Extraction Note 39: Comparison of Sensitivity Of Headspace GC, Purge and Trap Thermal Desorption and Direct Thermal Extraction Techniques For Volatile Organics Note 38: A New Micro Cryo-Trap For Trapping Of Volatiles At the Front Of a GC Capillary Column Note 37: Volatile Organic Emissions from Automobile Tires Note 36: Identification Of Volatile Organic Compounds In a New Automobile Note 35: Volatile Organics Composition of Cranberries Note 34: Selection Of Thermal Desorption and Cryo-Trap Parameters In the Analysis Of Teas Note 33: Changes in Volatile Organic Composition in Milk Over Time Note 32: Selection and Use of Adsorbent Resins for Purge and Trap Thermal Desorption Applications Note 31: Volatile Organic Composition in Several Cultivars of Peaches Note 30: Comparison Of Cooking Oils By Direct Thermal Extraction and Purge and Trap GC/MS Note 29: Analysis Of Volatile Organics In Oil Base Paints By Automated Headspace Sampling and GC Cryo-Focusing Note 28: Analysis Of Volatile Organics In Latex Paints By Automated Headspace Sampling and GC Cryo-Focusing Note 27: Analysis of Volatile Organics In Soils By Automated Headspace GC Note 26: Volatile Organics Present in Recycled Air Aboard a Commercial Airliner Note 25: Flavor and Aroma in Natural Bee Honey Note 24: Selection of GC Guard Columns For Use With the GC Cryo-Trap Note 23: Frangrance Qualities in Colognes Note 22: Comparison Of Volatile Compounds In Latex Paints Note 21: Detection and Identification Of Volatile and Semi-Volatile Organics In Synthetic Polymers Used In Food and Pharmaceutical Packaging Note 20: Using Direct Thermal Desorption to Assess the Potential Pool of Styrene and 4-Phenylcyclohexene In Latex-Backed Carpets Note 19: A New Programmable Cryo-Cooling/Heating Trap for the Cryo-Focusing of Volatiles and Semi-Volatiles at the Head of GC Capillary Columns Note 18: Determination of Volatile Organic Compounds In Mushrooms Note 17: Identification of Volatile Organics in Wines Over Time Note 16: Analysis of Indoor Air and Sources of Indoor Air Contamination by Thermal Desorption Note 14: Identification of Volatiles and Semi-Volatiles In Carbonated Colas Note 13: Identification and Quantification of Semi-Volatiles In Soil Using Direct Thermal Desorption Note 12: Identification of the Volatile and Semi-Volatile Organics In Chewing Gums By Direct Thermal Desorption Note 11: Flavor/Fragrance Profiles of Instant and Ground Coffees By Short Path Thermal Desorption Note 10: Quantification of Naphthalene In a Contaminated Pharmaceutical Product By Short Path Thermal Desorption Note 9: Methodologies For the Quantification Of Purge and Trap Thermal Desorption and Direct Thermal Desorption Analyses Note 8: Detection of Volatile Organic Compounds In Liquids Utilizing the Short Path Thermal Desorption System Note 7: Chemical Residue Analysis of Pharmaceuticals Using The Short Path Thermal Desorption System Note 6: Direct Thermal Analysis of Plastic Food Wraps Using the Short Path Thermal Desorption System Note 5: Direct Thermal Analysis Using the Short Path Thermal Desorption System Note 4: Direct Analysis of Spices and Coffee Note 3: Indoor Air Pollution Note 2: Detection of Arson Accelerants Using Dynamic Headspace with Tenax® Cartridges Thermal Desorption and Cryofocusing Note 1: Determination of Off-Odors and Other Volatile Organics In Food Packaging Films By Direct Thermal Analysis-GC-MS
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- Note 30: Comparison Of Cooking Oils By Direct Thermal Extraction and Purge and Trap GC/MS (This Page)
INTRODUCTION
Volatile and semi-volatile organic compounds present both in the matrix and the headspace aroma are primarily responsible for the flavor/fragrance qualities of commercial cooking oils. There is a concern in the food industry over the quality as well as the level of residual solvents that may be present in cooking oils due to plant origin, plant maturity, adulteration or dilution of the final product. In determining an oil's plant origin and assessing its overall flavor quality, it would be extremely advantageous to have a reliable and efficient method for the detection, identification and quantification of the volatile organic compounds responsible for the unique flavors and aromas in these oils. Because oils possess highly characteristic aromas due to specific volatile organic components, it can be anticipated that the chemical analysis of the aroma and flavor components of a given oil could give a fingerprint which could be dependent on the fruit or floral source. In previous studies of flavors and aromas in oils and food products, headspace GC techniques have been the methods of choice. However, headspace techniques are limited in their level of detection and identification of many organic volatiles, especially the semi-volatile organics.
More sensitive analytical techniques are needed to profile and identify flavors, fragrances, off-flavors, off-odors and potential contaminants that may be present as flavor and fragrance additives at lower concentrations. The purge and trap (P&T) technique permits the analysis of a wider range of both volatile and semi-volatile organic compounds and is more sensitive by a factor of at least 100 as compared to the static headspace technique. In addition, a new technique entitled Direct Thermal Extraction using a thermal desorption apparatus attached to the injection port of a GC/MS system permits the direct thermal extraction of volatile and semi-volatile organics directly from small sample sizes (mg) without the need for solvent extraction or other sample preparation. The samples are ballistically heated and together with the carrier gas flow through the samples the volatiles are outgassed into the injection port and onto the front of the GC column for subsequent analysis via the GC and/or GC/MS. For this study, cooking oils were analyzed by both the Direct Thermal Extraction and P&T techniques to determine the best suitable technique for possible development of a quality control method for the food industry. The volatile organics present in the oils were quantified using matrix spiked deuterated internal standards.
Figure 1 - Purge & Trap Apparatus
Instrumentation
Samples to be analyzed were collected using a Scientific Instrument Services Purge and Trap System. This apparatus (Fig. 1) consists of a sparge gas inlet connected to a stainless steel purging needle that is inserted through an adapter fitting into a 10 ml test tube. A dry purge gas inlet is located at a right angle to the sparge gas inlet at the top of the apparatus. This can be left in the closed or open position. The purpose of the dry purge is to reduce the water vapor condensation on the adsorbent trap. Opposite the dry purge inlet is the connector for the glass-lined stainless steel (GLT) desorption tube containing the adsorbent resin. The Purge and Trap System also contains two ball rotameters with adjustable needle valves mounted on a stationary base and permits the visual indication and independent adjustment of the carrier gas flow to each of the gas inlets.
A new technique called Direct Thermal Extraction which utilizes a thermal desorption apparatus attached to the injection port of a GC/MS permits the direct thermal extraction of volatile and semi-volatile organic compounds directly from small sample sizes (mg) without the need for solvent extraction or other sample preparation. The sample is either placed inside a glass-lined stainless steel desorption tube between two glass wool plugs which simply hold the sample in place or injected directly into a desorption tube containing either a glass wool plug or an adsorbent resin, as Tenax®. The desorption tube containing the sample is attached to the Short Path Thermal Desorption System and a syringe needle attached. The sample is then ballistically heated and together with the carrier gas flow through the sample the volatiles are outgassed into the injection port and onto the front of the GC column for subsequent analysis.
All experiments were conducted using a Scientific Instrument Services model TD2 Short Path Thermal Desorption System accessory connected to the injection port of an HP 5890 Series II GC interfaced to an HP 5971 Mass Selective Detector. The mass spectrometer was operated in the electron impact mode (EI) at 70eV and scanned from 35 to 400 daltons during the GC run for the total ion chromatogram.
A short 0.5 meter by 0.53 mm diameter fused silica precolumn was attached to the injection port end of a 30 meter x 0.25 mm i.d. DB-5MS capillary column containing a 0.25 µm film thickness. The GC injection port was set to 250 degrees C and 5:1 split was used. The head of the column was maintained at -70 degrees C using a GC Cryotrap model 951 (Scientific Instrument Services, Ringoes, NJ) during the desorption and extraction process and then ballistically heated to 200 degrees C after which the GC oven was temperature programmed from 35 degrees C (hold for 5 minutes) to 80 degrees C at 10 degrees C/min, then to 200 degrees C at 4 degrees /min and finally to 260 degrees C at a rate of 10 degrees /min.
Experimental
Six brands of olive oil were analyzed by both Direct Thermal Extraction and P&T techniques to determine the most sensitive technique for possible development of a quality control method for the food industry. For quantification, an internal standard was spiked into the adsorbent traps after the sample had been isolated. No correction for extraction efficiency of recovery is achieved using this technique; however, it serves as a useful means of quantifying the levels of components present on the adsorbent traps.
Purge & Trap
Sample sizes of 1 ml of the various oils were pipetted into a 10 ml test tube and heated to 80 degrees C for 30 minutes. Samples were purged with high purity helium at 20 ml/min with an additional 25 ml/min dry purge using the S.I.S. Purge and Trap System (Fig. 1). Volatile analytes were purged from the liquid matrix and carried to a preconditioned 4.0 mm i.d. glass-lined stainless steel desorption tube packed with 100 mg of Tenax TA.
Direct Thermal Extraction
Approximately 10 ul of each of the samples to be analyzed by Direct Thermal Extraction were injected into a 4.0 mm i.d. glass-lined stainless steel desorption tube containing 25 mg of Tenax TA (Fig. 2). The samples were then purged for 5 minutes at 80 ml/min to remove any moisture from the traps.
Figure 2 - Adding An Internal Standard To Desorption For Quantitation Of Analytes
Once the samples were collected in the desorption tubes, they were spiked with a mixture of 100 ng of d-8 toluene, 200 ng of d-14 cymene and 50 ng of d-8 naphthalene internal standard by injecting 1 ul of the stock solution in methanol by syringe injection into the Tenax matrix. An additional purging of 120 ml of purge gas was required to remove the methanol from the Tenax trap.
The desorption tube with sample and internal standard were then attached to the Short Path Thermal Desorption System and a syringe needle attached. The desorption tube was injected into the GC injection port at desorption block temperatures of 220 degrees C for 5 minutes and a flow rate of 5 ml/min for samples collected via purge and trap. For samples to be analyzed by Direct Thermal Extraction, the desorption block temperatures were set at 200 degrees C.
Results and Discussion
Six different manufacturers of olive oil were analyzed by Direct Thermal Extraction and P&T techniques to identify, compare and quantify the volatile organics present, and from the data, determine the most sensitive method of analysis. Table I shows the VOC's detected by each technique and the relative amounts of each of these compounds in each cooking oil analyzed. Over 200 volatile organics were identified in the various oils studied. Most of the cooking oils studied produced 50 or more volatile organics which were identified in addition to many more that were either too weak to identify or in which a good NBS library match was not achievable (Figs. 3 & 4). The cooking oils were found to contain numerous straight and branched chain hydrocarbons, aldehydes, alcohols, ketones, esters and furans in addition to many benzene derivatives. Significant differences in the volatiles present from the different manufacturers occurred in these olive oils. Although many of the same volatiles are present in all of these oils using either Direct Thermal Extraction or a Purge and Trap technique, there is significant variation in the quantities as well as the variety of volatile organics present. This variation could be due to the origin and maturity of the harvested olive fruits as well as differences in the manufacturing processes.
Table I. Relative Amounts of Volatile Organics in Cooking Oils
A AX B BX C CX D DX E EX F FX
1. Pentane x 2.3k 38.2 15k 49.9 20k 45.0 22k 37.2 26k x 23k
2. Butanal 3.3 x x x 3.9 569 15.5 x x x 4.1 x
3. Hexane 18.4 42k x 4.9k x 2.1k x 3.4k 95.3 4.7k x 3.3k
4. Ethylacetate 165 x 15.9 x 1.3 x 82.6 x 133 x 76.2 x
5. 3-methyl-butanal 11.8 x x x x x 21.7 x 18.6 x 27.9 x
6. 2-methyl-butanal 11.2 x x x x x 22.7 x 20.0 x 17.6 x
7. 3-pentanone 62.5 x x x x x x x x x 134 x
8. Heptane x 30k x 36k x 22k x 40k 390 58k x 33k
9. Pentanal 48.7 x 50.8 68.1 x 295 x x x x x x
10. d-8-toluene internal stardard
11. Toluene 28.3 x 19.1 x 9.1 x 22.7 x 60.7 x 28.6 x
12. 1-octene x x 3.8 1.9k 14.5 777 24.8 1.8k 63.2 5.0k 24.9 1.3k
13. 2-octene 17.8 x x x x x x x x x x x
14. Octane x 57k 228 53k x 33k x 59k 3.1k 93k 245 52k
15. Hexanal 516 x x x 319 x 1.9k x x x 366 x
16. (E)-2-octene x x x x x x x x 147 x x x
17. (Z)-2-octene x x x x x x x x 79.3 x x x
18. E-2-hexenal x 1.7k 120 1.5k 8.8 1.1k 689 2.0k x 4.3k 1.8k 3.7k
19. Z-3-hexenal 869 x x x x x x x 1.3k x x x
20 (Z)-3-hexen-l-ol 88.2 x x x x x x x x x x x
21. 4-hexen-l-ol x x x x x x 117 x 26.0 x x x
22. (E)-2-hexen-l-ol 436 x 8.9 x x x 183 x 249 x 286 x
23. 2-heptanone 48.6 556 17.5 1.6k 17.6 569 x 1.0k 62.0 1.8k 51.3 1.0k
24. Styrene x x x x x x 175 x x x x x
25. Heptanal 46.1 3.7k 15.9 12k 58.4 4.5k 227 8.6k 128 1.4k 52.1 4.2k
26. (E)-2-heptenal 23.1 8.6k 20.9 13k x 26k x x 200 x 24.6 x
27. (Z)-2-heptenal x x x x x 6.5k 124 10k x 2.3k x 1.9k
28. Benzaldehyde x 3.3k x 779 x 354 x 1.3k x 2.3k x 1.9k
29. 2-pentyl-furan x 1.5k x 12k 35.4 1.6k 149 2.1k x 2.9k x 1.6k
30. Octanal x 5.4k x 2.9k 43.5 4.9k 174 9.3k x 16k x 6.5k
31. (Z)-3-hexen-l-ol x x x x x x x x 227 x x x
32. (Z)-3-hexen-l-ol, 247 x x x x x x x x x 193 x
acetate
33. (Z)-4-hexen-1 -ol x x 18.0 x x x x x x x x x
34. Acetic acid, 8.07 x x x x x 14.9 x 64.3 x 78.2 x
hexyl ester
35. d-14 cymene internal stardard
36. Limonene 11.8 x 10.7 x 2.0 x x x 286 1.1k 6.9 x
37. (E)-2-octenal x 4.4k x 5.6k 9.2 5.1k 138 5.9k 49.8 9.2k x 5.5k
38. Nonanal 84.7 14k 18.9 23k 68.6 11k 334 21k 307 28k 63.5 16.3k
39. trans-2-dodecenal x 573 x x x 413 x x x 858 x x
40. (E)-2-nonenal x x x x x x x x x x x x
41. (Z)-2-nonenal x x x x x x x 1.3k x x x x
42. d-8-naphthalene internal stardard
43. 1 -octanol x x x x x x x 4.1k x x x x
44. cis-undec-4-enal x 2.2k x x x x x x x x x x
45. methyl-cyclo- 38.8 x x x x x 17.8 x x x x x
heptane
46. (2)-2-decanal 7.6 x x x x x x x x x 2.8 x
47. 2-cyclohexen-1 -ol x x x 19.9 x 28.8 x 34.8 x x x
48. (E)-2-decenal x 10k x 6.9k x 4.1k x 20k x 11k x 6.5k
49. Decadienal x 4.1k x 1.9k x 1.7k x 6.2k x 2.9k x 2.6k
50. trans,trans-nona- x 6.1k x 2.5k x 3.1k x 8.9k x 4.6k x 3.9k
-2,4-dienal
51. 2-undecenal 8.2 7.3k x 6.9k 16.8 4.5k 11.4 19k x 10k 1.2 5.9k
52. Farnesene x 1.1k x x x x x 2.1k x 1.0k x 638
The aliphatic C6 compounds hexanal, (E)-2-hexenal and (Z)-3-hexenal, which
contribute greatly to the green notes of the aroma, were detected by Purge
& Trap GC/MS in each of the cooking oils (Fig. 3). In addition to trace
amounts of hexanal and (Z)-3-hexenal, higher concentrations of (E)-2-hexenal
as compared to the P&T technique were found in the cooking oils using
the Direct Thermal Extraction technique (Table I). These compounds and
corresponding hexyl esters have previously been reported in great quantities
in the volatile components of olive oils. It has been assumed for a long
time that unsaturated fatty acids are the precursors of these volatile
compounds.
Figure 3 - Volatile Organics as determined by Purge & Trap
The aliphatic compounds heptanal, octanal and nonanal were also identified by Purge & Trap GC/MS in each of the cooking oils (Fig. 3). However, much higher concentrations of these compounds were detected using the Direct Thermal Extraction technique (Table I). Previous reports indicate that several aldehydes and ketones may be of importance for the development of rancid flavor. The branched aldehydes 2-methyl-butyraldehyde and 3-methyl-butyraldehyde, which contribute to the fruity flavor notes, were found in Brands A, D, E and F using the Purge & Trap technique (Fig. 3). However, these compounds were not detected by Direct Thermal Extraction. Linear alkenes such as 1- and 2-octene from lipid oxidation decomposition products were also detected in the cooking oils using both techniques (Figs. 3 & 4), with appreciably higher concentrations detected by Direct Thermal Extraction (Table I).
Pentane, hexane, heptane and octane were found in significantly higher concentrations in the olive oils when using the Direct Thermal Extraction technique (Table I). When compared to the Purge & Trap technique for the presence of these hydrocarbons, Direct Thermal Extraction was more sensitive by a factor of at least 1000. It has been previously reported that octane concentrations generally increased with time during storage. In addition to the increased sensitivity found when using the Direct Thermal Extraction technique as compared to the Purge & Trap technique, very high concentrations of higher molecular weight compounds such as (E)-2-decenal, decadienal, trans, trans-nona-2,4-dienal and 2-undecenal were identified via Direct Thermal Extraction in the olive oils (Fig. 4). These compounds contribute to the flavor and aroma of the cooking oils and are the result of fatty acid decomposition.
Figure 4 - Volatile Organics as determined by Direct Thermal Extraction
Conclusion
Direct Thermal Extraction has been utilized for the identification and quantification of volatile organics, aromas and flavor components in olive oils. This analytical technique can be utilized for the quality control during the production of the cooking oils as well as a technique for the detection of adulteration or dilution of these oils. The chromatograms produced can provide for a chromatographic fingerprint for the comparison of the cooking oils to determine origin, compare different manufacturers, or for quality control. Many kinds of flavors are used in the food industry, and there is a demand for new and improved ones, especially natural ones. Such a source are oils which can produce a variety of flavors. The Direct Thermal Extraction technique offers several unique advantages over the Purge and Trap technique including greater sensitivity and the detection of a wider range of volatile organics including higher molecular weight compounds and is more sensitive by a factor of at least 1000 as compared to the Purge and Trap technique. This technique can easily be incorporated into troubleshooting techniques to detect problems in a wide variety of commercial food products, to compare various competing manufacturers products as well as the implementation of a quality control program for the food industry.