Heart-Cutting HC-GC/MS

Why Heart-Cutting After all, it does add to the complexity of the analysis and often results in multiple analyses of a single sample. Is it worth the extra time to analyze a sample one fraction at a time HC-GC/MS utilizes the EGA thermogram to define thermal zones of evolving compounds. 

Each thermal zone can be sampled or vented independently. The analysis of each thermal zone yields a chromatogram containing only those compounds evolving from the sample of the selected temperature range.There are two scenarios which clearly show the benefits of using Heart-Cutting (HC) GC/MS. The first is when the detailed characterization of a sample is required. What is the composition of the sample If this sample is analyzed without using HC, the data is a composite of everything present in the sample. It is difficult to identify the base polymer (forget about using library search algorithms). It is a challenge to differentiate between pyrolyzates, additives and/or impurities. The likelihood of co-elutions, mis-identifications and inaccurate integrations is high. 

In short, a little time is saved, but the time necessary to process the data increases, and even under the best circumstances, the data quality is suspect.The second scenario addresses the situation that exists when there is interest in a short list of target compounds in a complex matrix. Is compound XYZ present in the sample and at what concentration Without HC, the entire sample must be analyzed, which takes time. And still, there may be issues with respect to co-elutions, mis-identifications and inaccurate integrations. It is much more difficult to find a suitable internal standard or to develop a standard addition calibration.Both of these situations take time and generate volumes of data to process and interpret. 

The use of HC-GC/MS will greatly simplify the data set, yield simpler, higher quality chromatographic data and reduce data processing time. In short, higher quality data in less time equals laboratory productivity. 

Slicing EGA Thermogram into Separate Temperature Zones

HC-GC/MS is the most powerful technique for performing reverse engineering and competitive deformulation.  It provides the scientist with detail organic composition of any sample matrix.