Buck Scientific, Inc. Seminar in ANALYTICAL INSTRUMENTATION for Spectroscopy & Chromatography: GAS CHROMATGRAPHY GAS CHROMATOGRAPHY (GC) Theory & Principle of OPERATION Using a pressurized “Carrier” Gas to push a Sample through a narrow Column filled or lined with a Polar “Packing” and Temperature Program; the VOLATILE Species present in that Sample can be properly separated for Identification and Quantitation on selected Detectors Basic GC Theory ALL Organic Molecules will have a characteristic Retention Time on a specific Column at a specific Temperature which can provide both Qualitative and Quantitative data Basic GC Design The ORIGINAL Gas Chromatograph from Perkin-Elmer in 1962 was 2 meters long and weighed ~100 kilos! They required large amounts of Gas and used up a big cylinder of Helium in only 3 days!! Hewlett-Packard introduced their GC system in 1965 (#5700), and still has the SAME basic hardware 35 years later; just in a “prettier” package (#6890)! Basic CHROMATOGRAPH Design ALL Analytical Chromatographs have several BASIC design components in common: INJECTION PORT COLUMN OVEN DETECTOR OUTPUT Buck GC Design BUCK Scientific developed the 600-series, small-sized GC back in 1988; using the SAME technology as Hewlett-Packard did in their large, heavy, high-$ system; but at 1/4 the size and 1/3 the price with NO loss of Analytical Data Quality. BUCK uses the SAME high-quality Columns to get the SAME high-quality Data. Buck GC Design The new BUCK 910-series GC Instruments use a very efficient, compact Oven with Electonic Pressure Control [EPC] for very specific requirements to insure very reproducible separations. “Open-Architecture” design allows BUCK to custommake ANY GC system rapidly and reliably. BUCK GC Hardware The advantages of the compact size, more efficient Oven design and precise Temperature control developed into a popular product line for all areas of Analysis = University, Pollution, Petrochemical, Polymer Science, Cosmetics, Food Technology; since we can assemble any required Hardware Configuration to meet the customer’s EXACT Analytical needs! SYSTEM Design The State-of-the-Art 910-series Gas Chromatographs from BUCK Scientific provide COMPLETE Flexibility and Capability for ANY GC analyses, with as many as 3 Injectors & up to 4 Detectors per unit! Any configuration can be designed to meet YOUR requirements for your Lab’s needs! Injectors • Injector - (Liquid or Gas Sample) – – – – – – – – Direct on-column Gas Sampling Valve Purge & Trap SPME Fibers Headspace Split/Splitless Thermal Desorption Autosamplers COLUMN Technology Advances in the design & construction of COLUMNS has opened up many new Applications that were not possible a few years ago….. Basic GC Columns • There are TWO Primary Modes of doing GC Analyses: – 1/8”Glass or Stainless Steel PACKED Column for Medium Resolution and large Sample Volumes – Fused Silica or Metal Capillary Colum for High Resolution and smaller Sample Volumes Basic GC Columns Developments in the fabrication of Metal Tubing has allowed Megabore (0.53mm) and Capillary (0.32mm) Columns to be designed in high-grade Stainless Steel (non-corrosive & unbreakable) instead of the more fragile & expensive Fused Silica. Research has also shown the METAL Columns have ~15% BETTER resolution than Silica! GC OVEN Features SMALL size Oven = LESS wasted Time & Energy • Heating Range (Ambient - 450°C) – Good for Petroleum “SIMDIS” work • FASTEST Heating Rate (= Faster analysis) • Column Fittings – 1/4” & 1/8” Packed – .53mm Megabore Capillary – Microbore Capillary GC Detectors • Thermal Conductivity Detector (TCD) – General Purpose, responds to all molecules – Detection levels of 100ppm - 100% – Useful for Permanent Gases • Catalytic Combustion Detector (CCD) – Very general use, does not require support gas • Helium Ionization Detector (HID) – More sensitive TCD type detector (10-25ppm) GC Detectors • Flame Ionization Detector (FID) – General Purpose, specific to hydrocarbons – Detection levels of 5ppm - 10% – Useful for General Organic Analysis • Photo Ionization Detector (PID) – Specific for Aromatic & Olefinic Compounds – Very sensitive (0.1ppm) – Useful for BTEX and Environmental Samples GC Detectors • Flame Photometric Detector (FPD) – Sulfur or Phosphorus bearing compounds – Detection levels of <0.1ppm – Useful in combustion streams and pesticides • Nitrogen Phosphorus Detector (NPD) – Specific to Nitrogen & Phosphorus bearing compounds (100ppb detection) – Useful for Pesticides, Herbicides & Drugs GC Detectors • Dry-Electrolytic Conductivity (DELCD) – Good linear response to Halogen atoms created in FID flame. Detection levels of 1-10ppb – Useful for Chlorinated HCs and Environmental • Electron Capture Detector (ECD) – *** NO LONGER AVAILABLE!!!! – Cost for Radio-Active License is Too HIGH! GC Chromatographic Controls • • • • • Higher Temperature = Closer Peaks Faster Heating = Faster Separation Higher Gas Flow = Closer Peaks Less Temp., Heating, Flow = Better Resolution Controlled Flow = Closer Peaks with minimum loss of resolution BALANCE Run-time & Separation! 910 GC - Product • • • • • • Laboratory grade GC systems Most economical pricing structure Compact, Rugged, Reliable Open architecture design for flexibility Model 310 half-size chassis for portability Various pre-configured systems 910 GC - Features • • • • • • PeakSimple Software Unlimited Temperature Programming Fast Cool from 400°C to 50°C in <5 min. Electronic Pressure Controls (EPC) Several Injector, Detector, and other options Single and dual-oven options 910-GC Features • Ideal for QA/QC for Manufacturing • Excellent for Environmental & Basic Research • Wide Variety of Sampling Techniques – SPME / Rapid, simple & accepted! – Continuous Flow Purge&Trap for VOCs – Programmable Headspace Analysis PeakSimple Software Features • • • • • • • Instant Peak Identification Multi-level Calibration Curves Auto Calibration Manually Re-integrate Chromatograms Click and Drag Retention Windows Overlay Chromatograms Control of internal/external devices GC APPLICATIONS • • • • • • • Environmental Monitoring Pharmaceuticals & Drugs Petrochemicals & Solvents Cosmetic Manufacturing Paints & Finishes Food Technology Education & University Research APPLICATIONS Since ALL Chromatographic Techniques are RELATIVE (not ABSOLUTE like Spectroscopy), GC is strictly for QUANTITATIVE determination of Known, Volatile Compounds only…. Since non-volatile materials will destroy the column. APPNOTE - Environmental SAMPLE: Insecticide Sprays for Bugs PREPARATION: ~100mg. of Spray Sample is placed in a Vial and diluted to 1ml. w/ Hexane ANALYSIS: 910-GC w/ Heated Injector, FID (for general Solvent) and DELCD (halogenated) RESULT: Use Reference Standards to ID & measure the components in the Spray APPNOTE - Environmental TWO Detectors confirm the ID of the primary PESTICIDE Compounds w/ Integrated Area for Concentration APPNOTE - Industrial SAMPLE: Paints & Lacquers for VOCs PREPARATION: None, weigh ~500mg. of Paint Sample into 40ml. VOC / Headspace Vial ANALYSIS: 910-GC w/ Headspace Sampler and FID Detector RESULT: Use Reference Standards to ID & measure the components in the Spray APPNOTE - Industrial Clean peaks due to high resolution of the Capillary Column give accurate data for the VOCs in this Sample APPNOTE - Food & Nutrition SAMPLE: Food & Vegetable Oils PREPARATION: Weigh ~500mg. of Oil into a Vial and convert to Fatty Acid Methyl Esters to determine the Saturation value for the Oil ANALYSIS: 910-GC, FID, Heated On-Column Injector RESULT: Use Reference Fatty Acid Standards to ID & measure those in the Oil APPNOTE - Food & Nutrition This is a Standard Method for Oil Analysis & the Data is used to Characterize the Oil Quality and Health properties