Seeking advice on gas chromatography response issues
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Two identical gas chromatographs; all parameters are the same, and both use TCD detectors. The same goes for the columns: Machine A uses old columns, while Machine B uses new ones. What I don’t understand is that under the same conditions, I injected the same sample; however, the peak profiles obtained from Machine A and Machine B were different. Specifically, on the new column, the peak at the expected position was very small. What I don’t understand is which machine has a problem. I suspect that there’s a problem with the new column in Machine B, or that the column or detector in Machine A is contaminated. The latter is unlikely, though, since this sample is used every time. I’m sure there’s a problem with the new column, or there’s a problem with Machine B. Everyone, please give some suggestions so we can discuss what the problem might be~
This is probably because your new column hasn’t fully aged yet. After it has aged, inject more of your samples into the column and observe for a few days (even when not in use, keep injecting samples). This will help determine whether the results match expectations. Generally speaking, there are always certain differences in the separation performance among columns; even for the same type of chromatograph, the detection sensitivity can vary slightly
Do you know what substance that peak represents? If so, you can add some standard samples of that substance to see how the peak shape changes; this will help determine the cause. Sometimes, due to prolonged use, old columns become ineffective. In such cases, you need to use a known sample to confirm this
It’s because the aging wasn’t done properly. Yesterday, I performed the aging process again, and that peak appeared