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| Note# |
Author |
Title/Description |
| 65 |
Matt Stevens |
Low
Level Ethylene in Air |
| 64 |
Matt Stevens and Hal Bellows |
Permanent
Gas Contaminants in Beverage Grade Carbon Dioxide |
| 63 |
Norm Kirshen and Lin Li |
Trace
Carbonyl Sulfide and Phosphine in Ethylene or Propylene |
| 62 |
Norm Kirshen and Lin Li |
Trace
Sulfur and Hydrocarbon Contaminants in Beverage Grade Carbon
Dioxide |
| 61 |
David Case and Matt Stevens |
ASTM
D4815 - The Determination of Oxygenated Compounds in Gasoline |
| 60 |
Kirshen |
The
Determination of Sulfur Gases in Natural Gas with PFPD |
| 59 |
Pachlhofer and Stevens |
Single
GC Gas Analysis Using Dual TCD and FID: Refinery Gas System
C for Comprehensive Gas Analysis |
| 58 |
Kirshen |
The
Determination of Vehicle Emissions in Exhaust Gases and Ozone
Precursors in Ambient Air with a Built-in Preconcentrator/GC
System |
| 57 |
Kirshen |
The
Determination of Trace Volatile Organic Compounds in Air
with an Integrated Preconcentrator/GC System |
| 56 |
Coe |
Sulfur
Compounds in Light Petroleum Liquids by Gas Chromatography
and PFPD |
| 55 |
Coe |
High
Temperature Simulated Distillation of Heavy Vacuum Residues
and Crudes |
| 54 |
Coe |
Rapid
Determination of Light Hydrocarbons in Crude Oil |
53
SPME 6 |
Penton |
Characterization
of Flavor Components in Wines with SPME, GC and GC/MS
Key Words: SPME, 8200 AutoSampler, Wine, Foods & Flavors,
GC/MS |
52
SPME 5 |
Penton |
Analysis
of Therminol in Water using Solid Phase Microextraction
Key Words: SPME, Therminol, Biphenyl, Diphenyl Oxide, Water |
51
SPME 4 |
Penton |
Flavor
Analysis of a Fruit Beverage with Automated Solid Phase Microextraction
Key Words: SPME, 8200 AutoSampler, Foods and Flavors |
50
SPME 3 |
Penton |
Determination
of a Wide Range of Organic Impurities in Water with Automated
Solid Phase Microextraction
Key Words: SPME, 8200 AutoSampler, Volatiles, Semivolatiles |
49
SPME 2 |
Penton |
Determination
of Residual Solvents in Pharmaceuticals with Automated Solid
Phase Microextraction
Key Words: SPME, 8200 AutoSampler, Beverages, Food
Description: This note describes the use of solid phase
microextraction (SPME) for determining organic volatile
impurities in pharmaceutical
compounds. In addition to the solvents listed in the United
States Pharmacopeia (USP) National Formulary, several additional
solvents were considered to conform to compounds actually
used in pharmaceutical companies. These were ethanol,
acetone, isopropanol
and toluene. The results, which included a recovery study
on two pharmaceutical compounds, indicated that SPME
easily met
the precision and sensitivity requirements of the USP and
is a good alternative to liquid injection or static
headspace. An automated SPME system is considerably less
expensive and
far more compact than a dedicated static headspace system,
and the problems of injecting aqueous samples into a GC
are avoided. |
| 48 |
Penton M. van Ryckeghem |
Evaluation
of a SPI Dual-Column System for the Determination of Selected
PCB Congeners in Mineral Waste Oil
Key Words: SPI, PCBs, ECD, Dual Columns
Description: As technical products, PCBs are a mixture
of more than 100 single components. Theoretically, 209 isomers
are
possible. In this application note, a method for the determination
of PCBs in mineral waste oil is described. Seven PCB congeners
(28, 52, 101, 118, 138, 153, 180) which are used as indicator
components for legal tolerance levels of PCB concentrations
in mineral oils, are determined with a dual-column SPI system
and dual electron capture detection. The method was applied
to a mineral waste oil sample that was fortified with ppm
levels of a technical PCB mixture. |
47
SPME 1 |
Penton |
Profiling
Flavors in Alcoholic and Non-Alcoholic Beverages with Automated
SPME
Key Words: Solid Phase Microextraction, SPME, 8200 AutoSampler,
Beverages Food
Description: Flavors in foods and beverages are monitored
by static headspace GC and occassionally by thermal desorption
or purge and trap. The result is a "fingerprint" chromatogram
that can be examined to determine if the particular sample
meets the standards set by the manufacturer, or if components
are present that might adversely affect the taste of the
product. Solid Phase Microextraction (SPME), a new technique
for introducing analytes into a GC, is used in this application.
The note illustrates that SPME is suitable for "fingerprinting" foods
and flavors, and offers several advantages over competing
techniques. |
| 46 |
Penton |
Determination
of Volatile Organic Solvents in Water by Headspace Sampling
with the 8200CX AutoSampler
Key Words: Ambient Headspace, 8200 AutoSampler, Residual Organic
Volatiles
Description: The Varian 8200 CX AutoSampler can be easily
modified to function as a headspace sampler for determining
organic volatiles in an aqueous matrix. Data is presented
comparing precision and sensitivity of this technique to
results obtained with a heated headspace system and direct
aqueous injection. The test sample and choice of column
was based on Methods IV and V of the United States Pharmacopeia
(USP) for determination of organic volatiles in pharmaceuticals. |
| 45 |
C. & J. Jennison |
Analysis
of BTX in Soil with Automated Headspace and PID/FID
Key Words: BTX, PID, FID, Genesis
Description: Analysis of BTXs and gasoline in soil with
the Genesis Headspace sampler. Linearity data is given for
xylenes
(100 ppb - 100 ppm). |
| 44 |
Penton |
GC
Determination of Halogenated Pesticides with Dual Columns
and Dual ECDs According to Contract Laboratory Procedure
(CLP) Requirements
Key Words: CLP Requirements, Pesticides, Retention Time Precision,
SPI
Description: In March 1990, the EPA issued the 3/90 State
of Work defining a procedure for GC determination of pesticides
and arochlors (1). Contract laboratories bidding for this
work not only are required to follow the analytical procedure
detailed in the document but must also demonstrate that
their results meet stringent standards of retention time
stability,
resolution and detector linearity. This publication describes
analytical conditions and presents data, showing that the
CLP requirements were met using a Varian Star GC system. |
| 43 |
Penton |
Automatic
Injection of Difficult Samples: Fine-tuning the Conditions
for Volatile Samples
Key Words: 8200, AutoSampler, SPI, Volatile, Pentane, CS2
Description: Describes the optimization of parameters for
injecting volatile samples with the 8200 utilizing a sample
consisting
of 1:500 (v/v) of a nonpolar test mix in n-pentane and in
CS2. To inject a volatile sample, the user need only to select
the "volatile" mode.
There is also a "user-defined" mode that allows the
analyst to make additional changes if desired. |
| 42 |
Penton |
Automatic
Injection of Difficult Samples: Fine-tuning the Conditions
for Viscous Samples
Key Words: 8200, AutoSampler, SPI, Viscous, Ethylene Glycol
Description: This note describes the optimization of parameters
for injecting viscous samples with the 8200. To inject a
viscous sample, the user need only to select the "viscous" mode.
There is also a "user-defined" mode that allows the
analyst to make additional changes if desired. The sample used
was 500ppm (v/v) diethylene glycol in ethylene glycol. |
| 41 |
Penton |
Optimization
of Conditions for the Determination of Ethanol in Blood by
Static Headspace GC
Key Words: Static Headspace, Blood Alcohol, Genesis, Ethanol
Description: GC and headspace conditions are given for
determination of ethanol in water with n-propanol internal
standard. |
| 40 |
Penton |
Optimization
of Parameters in Static Headspace GC
Key Words: Static Headspace, Parameter Optimization, Genesis,
Method Optimization Mode
Description: The purpose of this note is to show how precision
and sensitivity can be maximized when utilizing SHS GC
by selecting the optimal parameters for the particular analysis.
Parameters discussed are: 1) Sample preparation procedures
to maximize sensitivity and precision. 2) Factors controlled
by the headspace instrumentation: a) Sample equilibration
time and the effect of mixing the sample during the equilibration
period. b) Effect of sample vial and transfer line temperatures. |
| 39 |
Penton |
Determination
of Solvents in Pharmaceuticals by Static Headspace GC
Key Words: Capillary GC, Static Headspace, Volatile Organics,
Pharmaceuticals
Description: In late 1990, The US Pharmacopeia released
two methods for determining organic volatile impurities in
pharmaceutical
compounds by gas chromatography. The first method involved
a liquid-liquid extraction prior to the analysis, and the
second utilized the purge and trap or dynamicheadspace technique.
This Application Note demonstrates that static headspace
(SHS)
offers an alternative approach to this determination. |
| 38 |
Carmichael Schumacher |
Single-Column
Analysis with Natural Gas System A
Key Words: Late Backflush, IP345, Temperature Programmed
Description: A standard natural gas analysis, using a single
column, temperature programming and late backflush (IP345). |
| 37 |
Penton |
Determination
of Chlorinated Acidic Herbicides with a Two Column SPI System
and Dual Electron Capture Detection
Key Words: Herbicides, Pesticides, Acidic Pesticides, SPI,
Dual Column, Dual ECD
Description: The compounds listed in EPA Method 515.1 are
acidic and include phenols and carboxylic acids. Although
phenols ususally can be determined on non-polar fused silica
columns, carboxylic acids require derivatization. A derivatization
procedure is described which utilized Methyl-8™ (dimethylformamide
dimethyldiacetal) instead of the diazomethane listed in
the EPA method. This reagent is simpler to use and less
hazardous
than diazomethane. The pesticides were separated on two
columns connected to one injector for simultaneous analysis
and confirmation. |
| 36 |
Thompson |
Dual
Channel Analysis of Refinery Gas: Refinery Gas System B
Key Words: Refinery Gas, Unsaturated Hydrocarbons, Hydrogen
Sulfide, Carbonyl Sulfide, PLOT Alumina Column
Description: Dual GC approach for analysis of refinery
gas, including H2S and COS, using PLOT alumina column, dual
TCD
and FID. |
| 35 |
Schumacher Thompson |
Fast
Isothermal Analysis of Transformer Gas
Key Words: Dissolved Gases, Methanizer, ASTM Methods D3613,
D2945, D3612
Description: Measurement of dissolved gases, extracted
from electrical insulating oil (ASTM 3612) using methanizer
and
TCD/FID. |
| 34 |
Schumacher Thompson |
Single
Channel Analysis of Refinery Gas: Refinery Gas System A
Key Words: Refinery Gas, Unsaturated Hydrocarbons, Methanizer,
PLOT Alumina Column
Description: Measurement of saturated and unsaturated hydrocarbons,
elemental and inorganic gases in refinery gas using a methanizer,
PLOT alumina column, and TCD/FID. |
| 33 |
C. Jennison |
The
Analysis of Low Level Residues of Toxaphene in Water
Key Words: Environmental Residue Analysis, Toxaphene, Dual
Channel, SPI, 3500, ECD
Description: Toxaphene is a complex mixture of polychlorinated
camphene [camphene, C10H16, is a norbornane (or bicycloheptane)
structure that is 2,2-dimethyl-3-methylene substituted.]
Toxaphene generates a GC profile similar to a PCB (a large
number of closely spaced peaks). Even after a silica gel
cleanup of a methylene choride extract, toxaphene must
be identified and quantitated against a complicated background
of other ECD responsive analytes. The App Note describes
a dual column (different polarity)/dual ECD method with
special
two channel analysis in which the ratio of response from
the two channels confirms the identity of toxaphene peaks. |
| 32 |
Almasi, Kirshen |
The
Determination of Volatile Organic Compounds in Ambient Air
Key Words: Air Analysis, EPA Method TO-14, VOCs, Cryogenic
Concentration
Description: Describes EPA Method TO-14 using built-in
cryotrapping device (VTAT) and associated valving, separation
on capillary
column and detection with FID/ECD detectors. |
| 31 |
Schumacher Thompson |
Extended
Analysis of Natural Gas and Natural Gas Liquids
Key Words: Industrial, Natural Gas, Natural Gas Liquids, Extended
Analysis, GPA, GPA Standard 2186, GPA Standard 2286
Description: Extended capillary single-channel analysis
of natural gas and natural gas liquids, including separation
of oxygen and hydrogen sulfide. |
| 30 |
Penton |
Determination
of Nitrosamine Contaminants in a Herbicide: Advantages of
the 8100 AutoSampler for Highly Concentrated Samples and
Nitrogen Detector with Programmable Bead Current
Key Words: Industrial, Nitrosamines, Herbicides, SPI, TSD Programmable
Bead Current, 8100 Concentrated Samples, Trifluralin, Trefla
Description: Nitrosamine contaminants are determined in
a widely used herbicide without sample cleanup. The
SPI and the TSD are used. The bead current
to the TSD is turned on and off without compromising the results. |
| 29 |
Schumacher Thompson |
Analysis
of Natural Gas and Natural Gas Liquids
Key Words: Industrial, Natural Gas, Hydrogen Sulfide, Optional
Internal Volume Sample Valve (LSV), Gas Processors Association
(GPA), GPA Standard 2261, GPA Standard 2177
Description: Single-channel analysis of natural gas and
natural gas liquids provides O2 and N2 separation when required,
and early backflush of grouped heavier hydrocarbons. |
| 28 |
Penton |
A
Demonstration of Automated Solvent Flush Injection to Eliminate
Sample Discrimination in the Determination of Pesticides
by Splitless Capillary Injection
Key Words: Environmental, Pesticides, Dual Columns, 8100 A/S,
Solvent Flush
Description: This is a demonstration of the value of the
solvent flush technique in the 8100 AutoSampler. Using
a pesticide sample, it is shown that solvent flush minimizes
mass discrimination in hot splitless injection. |
| 27 |
Penton |
Screening
for Pesticides with Two Columns in a Split/Splitless Capillary
Injector: A Comparison of Two Techniques for Installing the
Columns
Key Words: Environmental,Pesticides, Dual Columns, Inlet
Splitting Technique
Description: Two columns are installed in a 1077 injector
in the splitless mode using 1) the technique of putting both
columns in the injector and 2) a "Pressfit" inlet
splitter. A comparison is made of the two techniques with
a pesticide test sample. |
| 26 |
Thompson |
Determination
of Sub-ppm Concentrations of CO and CO2 in Ethylene and Propylene
Key Words: Industrial, Ethylene, Propylene, CO, CO2, Methanizer
Description: Measurement of sub-ppm concentration of CO
and CO2 in polymer grade olefins by direct injection, catalytic
conversion to methane and detection by FID. |
| 25 |
Thompson |
Application
of a Variable-Temperature Adsorption Trap: Moisture in Elemental
and Other Gases
Key Words: Industrial, VTAT, Moisture, Water
Description: Measurement of moisture at ppm levels in pure
gases, using the VTAT. |
| 24 |
Almasi, Kirshen |
The
Analysis of Volatile Organic Chemicals According to EPA Method
502.2 without Cryofocusing
Key Words: Environmental, Method 502.2, VOCs, Purge & Trap,
ELCD, PID, Restek
Description: Using Purge and Trap, VOCs are chromatographed
on the Restek RTX-502.2 column, which needs no column
oven cryogenics. |
| 23 |
Penton |
Determination
of Neutral Lipids By High Temperature GC: Part II. Investigation
of Thermal Stability of Saturated and Unsaturated Triglycerides
During Separation by High Temp GC
Key Words: Industrial, Thermolabile Triglycerides, SPI,
High Temperature GC
Description: Column temperatures up to 410oC are used to
elute triglycerides containing saturated & unsaturated
fatty acids with minimal thermal degradation. The injector
is the
SPI. |
| 22 |
Penton |
Determination
of Neutral Lipids By High Temperature GC: Part I. Triglycerides
and Cholesteryl Esters in Foods
Key Words: Industrial, Lipids, Cholesterols, Triglycerides,
Food Analysis, SPI
Description: The determination of high-molecular weight
cholesteryl esters and intact triglycerides is demonstrated
in food samples.
The SPI is used. A sample cleanup procedure is described. |
| 21 |
Penton |
How
Much Sample is Lost in a Low Loss AutoSampler? (Automated
GC Injection With Minimum Sample Size)
Key Words: 8100 AutoSampler, Low Loss, 10 礚 Sample
Description: A rigorous proof statement that the 8100 can
deliver 8 1-礚 injections with good area count precision from a 10 礚
sample. |
| 20 |
Almasi, Kirshen |
The
Analysis of Volatile Organic Compounds in Air and/or Soil
Gas: Fixed Volume System
Key Words: Environmental, Air, Soil Gas, VOC, VTAT, PID, ECD,
ELCD
Description: Sub-part per billion levels of volatile organic
compounds are determined in air using pre-concentration of
a fixed volume (100 mL or 2 mL) of sample onto a VTAT and
chromatographing on a capillary column with PID and ECD or
ELCD. |
| 19 |
Almasi, Kirshen |
The
Analysis of Volatile Organic Compounds in Air: Variable Volume
System
Key Words: Environmental, Air, Soil Gas, VOC, VTAT, PID, ECD,
ELCD
Description: Sub part per billion levels of volatile organic
compounds are determined in air using pre-concentration of
a variable volume air sample on a variable temperature adsorption
trap, capillary column, and PID with ECD or ELCD. |
| 18 |
Carmichael |
Automated
Injection of Viscous Materials: The Advantages of Solvent
Flush Injection and Dual Solvent Wash
Key Words: Solvent Flush, Air Gap, Solvent Wash Viscous Samples, Splitless
Injection, AutoSampler, Carryover
Description: Use of an 8100 AutoSampler to generate improved
peak shape and minimize sample carryover to aid method precision. |
| 17 |
Penton |
Comparison
of Discrimination and Precision on Three Capillary Injectors:
The Septum-Equipped Temperature Programmable Injector (SPI),
the Temperature Programmable On-Column Injector (TPOCI) and
the Splitless Injector
Key Words: Mass Discrimination, SPI, TPOCI, Splitless, High
Boiling Compounds
Description: Normal alkanes from C7 to C46 are separated
on a narrow-bore capillary column. Three capillary injectors,
the 1077 (splitless mode), temperature-programmed on-column,
and the SPI, are compared for precision and mass discrimination.
This is a proof statement that in the range studied, the
SPI performs as well as the on-column injector, while the
splitless injector exhibits serious mass discrimination. |
| 16 |
Almasi, Kirshen |
The
Analysis of Polynuclear Aromatic Hydrocarbons by Capillary
Gas Chromatography with the Septum-Equipped Programmable
Injector
Key Words: Environmental, PAH, PNA, SPI, PID, EPA Method 610
Description: Priority pollutant PAHs may be measured using
capillary columns, SPI and photoionization detector to give
detection levels that meet or beat EPA method 610 requirements.
|
| 15 |
Almasi, Kirshen |
The
Determination of Fixed Gases and Total Hydrocarbons in Soil
Gas and Air
Key Words: Environmental, Total Hydrocarbons, Air, Soil, Gas,
TCD, FID
Description: Fixed gases (O2, N2, CH4, CO2,) and total
hydrocarbons are measured in either air or soil gas using
a simple 2-loop
GSV with TCD and FID. |
| 14 |
Holmes |
Screening
of Trihalomethanes by Direct Aqueous Injection
Key Words: Environmental, Electron Capture, SPI, Direct
Aqueous Injection, Sheath Flow Cell Design, Haloforms,
DB624 (Cyanopropyl),
Injection Speed
Description: Haloforms in drinking water are determined
by directly injecting water into a capillary column with
subsequent
detection ?by two different designs of electron capture
detector. |
| 13 |
Penton |
Determination
of Low Levels of an Additive in Gasoline by Gas Chromatography
with the Septum-Equipped Programmable Injector (SPI)
Key Words: Industrial, Gasoline Additives, Selective Detection,
TSD, SPI, Thermolabile Compounds, 3500 GC
Description: A nitrogen-containing detergent added to commercial
gasoline is determined without sample cleanup. The SPI and
TSD are used. The compound is thermolabile but good precision
and linearity are achieved. |
| 12 |
Almasi, Kirshen |
The
Determination of Fixed Gases and Non-methane Organic Compounds
in Soil Gas and Air
Key Words: Environmental, NMOC, EPA Method 25, Hopcalite,
Air, Soil Gas.
Description: Fixed gases (CO, CH4, CO2) and nonmethane
organics are determined in either air at <1ppm or soil gas up to
percentage levels using EPA Method 25 technology. |
| 11 |
Penton |
Determination
of Trace Amounts of Thermolabile Compounds by Capillary GC:
Comparison of a Septum-Equipped Programmable Injector (SPI)
with a Hot Splitless Injector
Key Words: SPI, Thermolabile Compounds, Donike Test, Trimethylsilyl
Esters
Description: A test sample described in the literature
containing thermolabile compounds and stable compounds is
used to demonstrate
the ability of the SPI with nonvaporizing injection to
prevent thermal breakdown. Comparison is made with hot injection. |
| 10 |
Carmichael |
Characterization
of High Molecular Weight Hydrocarbons Using High Temperature
Gas Chromatography
Key Words: Industrial, Hydrocarbons, High Temperature, Simulated
Distillation, Physical Properties, 3410 GC, Aluminum Clad Columns
Description: High temperature analysis of hydrocarbons
with 341/650 combination using aluminum clad columns. |
| 9 |
Almasi, Kirshen |
Volatile
Organic Compounds in Water by Purge and Trap/Capillary Column
Gas Chromatography with Photoionization (PID) and Electrolytic
Conductivity Detectors (ELCD) in Series
Key Words: Environmental, Purge and Trap, DB-624, VOCOL, Column Selector,
Method 502.2
Description: Purge and Trap/megabore columns, DB-624, and
VOCOL, are demonstrated for their applicability to EPA Method
502.2. |
| 8 |
Carmichael |
Monitoring
of Combustible Gas Mixtures in an Effluent Gas Stream
Key Words: Industrial, Gas Analysis, Thermal Conductivity,
PLOT 530 μm, Methanizer, CO
Description: The use of a TCD at 5 ml/min flow rate with
a megabore PLOT column, in conjunction with a methanizer
and FID in series. |
| 7 |
Thompson |
Application
of a Variable Temperature Adsorption Trap: Determination
of COS in Propane or Propylene
Key Words: Industrial, VTAT, COS, Sulfur, Propane, Propylene,
FPD
Description: Measurement of COS at sub-ppm concentrations
in propane or propylene, using the VTAT. |
| 6 |
Thompson |
Application
of a Variable-Temperature Adsorption Trap: Determination
of Odorant Sulfur Compounds in Natural Gas
Key Words: Industrial, VTAT, Natural Gas, Odorants, Mercaptans,
FPD, Sulfur
Description: Improving detectability of sulfur odorants
in natural gas by concentration from a large volume by means
of the VTAT. |
| 5 |
Thompson |
Application
of a Variable-Temperature Adsorption Trap: THMs and Purgeable
Organics in Finished Water
Key Words: Environmental, VTAT, THMs, Purgeable Organics
Description: A standard purge and trap analysis using the
VTAT for purgeable organics in Finished Water. |
| 4 |
Almasi, Kirshen |
The
Analysis of Nitrogen and Phosphorous Containing Pesticides
by Gas Chromatography Using Dual Capillary Columns
Key Words: Environmental, Nitrogen-Phosphorous Pesticides,
507, Dual Capillary, TSD, Split/Splitless, Drinking Water,
EPA Method
Description: Nitrogen-phosphorous containing pesticides
that must be monitored in drinking water are screened and
confirmed
in one injection saving time and analysis cost. |
| 3 |
Thompson |
Application
of a Variable-Temperature Adsorption Trap: Safrole in Smoked
Ham
Key Words: Industrial, VTAT, Trapping
Description: An example of stripping a volatile compound
(Safrole) from a nonvolatile matrix (smoked ham), subsequent
concentration
by VTAT and determination by GC. |
| 2 |
Penton |
Monitoring
Acrylonitrile in Waste Water with Headspace GC
Key Words: Environmental, Industrial, Headspace A/S, Wastewater,
Acrylonitrile, TSD
Description: The Varian 8034 AutoSampler modified with
a 100 礚 syringe for headspace sampling is used to determine
acrylonitrile in industrial wastewater. MDQ was 2 ppb. |
| 1 |
Holmes, Kirshen |
The
Screening and Confirmation of Organochlorine Pesticides Using
Dual Capillary Columns and Result Ratioing
Key Words: Environmental, Organochlorine, Pesticides, 508,
Dual Capillary, ECD, Split/Splitless, Drinking Water, EPA Method
508
Description: Organochlorine pesticides monitored in drinking
water are screened and confirmed in one injection saving
time and analysis cost. |
|
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