#Sequencher compare chromatograms how to#

Differences in Gas Chromatogram ModelsĪt a high level, depending on the type of sample and the desired outcome, gas chromatography analysis can use several different means of sample introduction, such as static headspace analysis, thermal desorption, and direct injection, as well as different types of detectors, such as flame ionization (FID), electron capture (ECD), and-of course-mass spectrometry.Īs a result, chromatograms can often differ in how they appear. The mass spectrometer detector then allows identification of a compound by mass spectrum obtained at the time of testing. In addition, unknown compounds are identified based on their retention times of known standards with other detectors. To overcome this challenge, our experts run standards with known concentrations of compounds to ensure accurate counts. However, it’s important to note that some compounds will have a better affinity with the detector and the peaks will appear larger than the actual concentration would be in relation to the other peaks on the chromatogram, which we often see in compounds that ionize readily. When looking at a GC/MS chromatogram, the area will be based on the number of counts taken by the mass spectrometer detector at the point of retention. Typically, the y-axis, or the area of the peak, is a reflection of the amount of a specific analyte that’s present. The Y-Axis: Concentration or Intensity Counts As a result, when comparing retention times from different analyses or different labs, it’s critical that the same parameters are used to ensure accuracy. flow rate, injection temperature, oven temperature, etc.), have a large impact on the retention time. The type of column used during the analysis, as well as the GC parameters (e.g. The peaks that are shown correspond to the time at which each of the components reached the detector. Usually, the x-axis of the gas chromatogram shows the amount of time taken for the analytes to pass through the column and reach the mass spectrometer detector.

#Sequencher compare chromatograms how to#

How to Read GC/MS Chromatograms The X-Axis: Retention Time This is called the stationary phase and it’s the level of attraction during this phase that causes components to separate and elute at different times, which shows as peaks on the resulting chromatogram. The gases then pass through a column, which is coated with material to attract the various components of the sample at varying degrees. Generally speaking, if a sample isn’t already in gas form, it’s introduced and volatilized in the injection port of the gas chromatograph. In order to understand GC/MS results, it’s helpful to know a little bit about how GC/MS analysis works. With that said, we’ve developed this handy guide to interpreting GC/MS data to help our customers-and anyone else who’s interested in knowing how to analyze a gas chromatogram.

Your lab should be providing you with detailed insights and actionable recommendations in an easy to understand format something Innovatech Labs prides itself on. Gas chromatography mass spectrometry (GC/MS) analysis is an effective testing and troubleshooting tool for many manufacturers across industries, helping identify and quantify the materials that make up a sample or uncover contaminants that impact product quality.īut when it comes to making sense of GC/MS analysis results, you may wonder how to read a gas chromatogram or how to interpret the results. Critical Medical Device Testing Services.Hard Drive Microcontamination Testing Services.Quality Control Testing for Manufactured Products.Outgassing Testing Services Prevents Critical Errors.Materials Characterization & Specialized Testing.Material Testing Services for Products and Components.Cleanliness Testing for Microcontamination.Thermal Gravitational Analysis (TGA) Lab Services.Electron Spectroscopy for Chemical Analysis (ESCA).Gas Chromatography Mass Spectrometry (GC/MS).Fourier Transform Infrared Spectroscopy (FTIR).Differential Scanning Calorimetry (DSC) to Measure Heat Flow.