GC Troubleshooting made easy by CHROMacademy an interactive GC tool for chromatographers

We developed the CHROMacademy GC Troubleshooter with busy chromatographers in mind.
In 3 simple steps we can help you overcome your instrument, separation and quantitation issues.

Step 1.Select from  over 40 different chromatographic symptoms which deal with separation, peak shape, baseline and quantitation issues

Step 2. Select from nearly 50 different instrument symptoms which deal with pressure and  flow problems as well as a host of inlet and detector issues.

Step 3.The troubleshooter returns a list of possible causes ranked by an algorithm, developed by chromatography experts. Each cause has a concise summary of the problem and recommended solutions. These solutions are supported by over 1000 references, feature articles and CHROMacademy content written by our highly experienced Gas Chromatography team.

 

Select up to 3 Chromatographic Symptoms. [Roll over for example chromatogram - click to select]

Separation & Quantitation Issues Resolution decreased Selectivity changed Sensitivity reduction - later eluting peaks Sensitivity reduction - earlier eluting peaks Reduced sensitivity (all peaks) with increased retention time Reduced sensitivity (all peaks) with normal retention time Peak area reproducibility poor Priming injections required to establish consistent peak area Non-linear quantitation Baseline Issues - See also Instrument Symptoms Baseline drifting (no discernible pattern) Baseline drifting to lower value Baseline falling away slowly after a high initial value Baseline drifting to higher value Baseline rising under temperature program control Baseline off-scale (high standing current) Baseline irregular shape: dip after solvent peak Baseline irregular shape: S-shaped Baseline irregular shape: square waves Baseline high frequency noise (non-detector related) Baseline spiking Baseline shift after solvent peak (non-detector related)

Peak Shape Issues Peaks broadening (loss of efficiency) Peaks clipping at bottom Peaks clipping at top Double / Split Peaks Shouldered Peaks Ghost (Extra) Peaks Broad Ghost (Extra) Peaks Chair-shaped Peaks Discrete high-intensity carry-over analyte peaks Negative Peaks (all peaks) No Peaks after solvent peak (non-detector related) No Peaks at all (non-detector related) Sample Peak Fronting Sample Peak Tailing Solvent Peak Tailing Retention Issues Retention times decreased Retention times increased Retention times variable

Select up to 2 Instrument Symptoms. [Roll over for graphic representation – click to select]

Pressure / Flow Issues Pressure / Flow - Variable carrier gas flow / pressure Pressure / Flow - cannot reach required pressure / flow Pressure / Flow - Pressure loss after injection Pressure / Flow - No flow FID Detector Issues FID: Sensitivity reduction FID: No response FID: Noisy baseline FID: Drifting baseline FID: Unstable baseline FID: Flame Ignition problems FID: Off-scale response ECD Detector Issues ECD: Sensitivity reduction ECD: No response ECD: Noisy baseline ECD: Drifting baseline ECD: Unstable baseline ECD: Negative dips after peaks ECD: Off-scale response ECD: Some negative peaks NPD Detector Issues NPD : Sensitivity reduction NPD: No response NPD: High background level NPD: Drifting baseline NPD: Noisy baseline NPD: Large negative baseline shift following the solvent peak NPD: Unstable baseline NPD: Negative hydrocarbon peaks NPD: Off-scale response

FPD Detector Issues FPD : Sensitivity reduction FPD: No response FPD: High background level FPD: Drifting baseline FPD: Noisy baseline FPD: Large negative baseline shift following the solvent peak FPD: Unstable baseline FPD: Off-scale response TCD Detector Issues TCD: Sensitivity reduction TCD: No response TCD: Noisy baseline TCD: Drifting baseline TCD: Unstable baseline TCD: Some negative peaks TCD: Off-scale response MS Detector Issues MS: Baseline off-scale MS: Low sensitivity MS: High background response MS: Unstable baseline MS: Off-scale response