Gas Chromatography Mass Spectrometry (GC/MS)

Gas Chromatography Mass Spectrometry (GC/MS) identifies volatile and semi-volatile compounds and separates them into individual components using a temperature-controlled gas chromatograph. During the process, a sample is injected into the chromatograph (or it may come from another sampling device) and passes through the chromatography column, which separates mixtures into individual components as they pass through at different rates. The result is a quantitative analysis of the components, along with a mass spectrum of each component.

Often compounds cannot be analyzed by a particular method, because they are not in a form amenable to the analytical technique. Evans Analytical Group® (EAG) has a number of alternative approaches to getting a sample into the GC/MS instrument.

• Dynamic Headspace Analysis (HSA) is used primarily for analyzing volatile compounds in matrices that cannot be directly injected into a gas chromatograph, including polymers, electronic components, wafers, biomedical devices, and environmental samples not suitable for direct injection. In dynamic HSA, the sample is placed in a closed chamber and heated to a specified temperature for a specified time. The outgassed components are then collected and analyzed by GC/MS.
• Pyrolysis analyzes nonvolatile organic compounds, such as wood, paper, or polymers. With this technique, the sample is heated rapidly to 750ºC or higher in order to thermally decompose it into smaller, more volatile fragments. Pyrolysis is frequently used to examine materials for the presence of additives, such as plasticizers, antioxidants, flame-retardants, UV-stabilizers, or sizing treatments applied to cloth samples.
• Solids Probe is a volatilization technique that places a nonvolatile sample under vacuum near the mass spectrometer’s ion source. As the molecules volatize during the heating time, they continuously enter the mass spectrometer’s source and are ionized similar to the standard GC MS technique. The disadvantage of this technique is there is no separation step.

EAG’s GC/MS service offering is unique, because we have a highly qualified scientific staff experienced at handling diverse, nonstandard samples. We are equally adept at handling the customary/federally regulated tests (e.g., FDA, EPA) as we are challenging one-off issues. We have analyzed many different materials, and we have intimate knowledge of the instruments and the best way to use them. Equally important, you can count on fast turnaround times, accurate data, and person-to-person service, so you will be sure to understand the information that you receive.

View Application Notes

Ideal Uses for GC/MS Analysis		Relevant Industries for GC/MS Analysis
Identifying and quantifying volatile organic compounds in mixtures Outgassing studies Testing for residual solvents Liquid or gas injections Evaluating extracts from plastics Evaluating contaminants on semiconductor wafers (thermal desorption)		Biomedical/biotechnology (primary) Electronics (primary) Aerospace Automotive Compound Semiconductor Data Storage Defense Displays Industrial Products Lighting Pharmaceutical Photonics Polymer Semiconductor Solar Photovoltaics Telecommunications
Strengths of GC/MS Analysis		Limitations of GC/MS Analysis
Identification of organic components by separating complex mixtures Quantitative analysis Trace-level determination of organic contamination (low to mid-ppb level for liquids and low nanogram level for solids (Dynamic Headspace Analysis)		Sample must either be volatile or capable of derivatization If the sample is not volatile (as in headspace, pyrolysis, or direct probe), then the analyzed material must be volatile

Application Notes