I use Restek Grob mixture often. Dicyclohexylamine is the component most likely to tail or broaden (usually broaden). I haven't figured out why this has been happening. The problem is intermittent and often the dicyclohexylamine peak shape is great, but I don't know what I did different to cause improvement or detriment to this peak shape.
Like several other components in the Grob test mix, dicyclohexylamine is testing for inertness. Amines can be particularly sensitive as well and problems with inertness can be the column, the inlet, and at times even the sample prep/handling. Even relatively small changes to any of these could cause changes in response/peak shape of dicyclohexylamine. I think the question to ask here is if the dycyclohexylamine response changes indicate a problem that is impacting your analysis. Does that probe represent compounds that you analyze? Does it predict behavior that you see elsewhere in your analysis?
Compounds like carboxylic acids, can be very difficult to get good peak shapes. Depending on the column phase, there may be columns specifically designed to work with acids that can help. Stabilwax-DA columns are an example. Derivitization is also used for some compounds to improve peak shapes - fatty acids are often methylated before being analyzed for this reason. Some analysts also do priming injections - injecting high concentration standards to help occupy active sites before doing their analytical injections. There are many options, but they can all have their pros and cons.
I use Restek Grob mixture often. Dicyclohexylamine is the component most likely to tail or broaden (usually broaden). I haven't figured out why this has been happening. The problem is intermittent and often the dicyclohexylamine peak shape is great, but I don't know what I did different to cause improvement or detriment to this peak shape.
Like several other components in the Grob test mix, dicyclohexylamine is testing for inertness. Amines can be particularly sensitive as well and problems with inertness can be the column, the inlet, and at times even the sample prep/handling. Even relatively small changes to any of these could cause changes in response/peak shape of dicyclohexylamine. I think the question to ask here is if the dycyclohexylamine response changes indicate a problem that is impacting your analysis. Does that probe represent compounds that you analyze? Does it predict behavior that you see elsewhere in your analysis?
If therotical plate fail mean what is troubleshooting
Your dog has cute tailing. Lol
Beautiful tip given by you, thank you
Glad you liked it!
Can you please make a video on fixing heat escaping error . Please!
There is also the case where the peaks will sometimes tail when doing splitless injections
What about chemicals with labile hydrogen such as carboxylic acid due to the column ? Is there a way to avoid peak tailing ?
Compounds like carboxylic acids, can be very difficult to get good peak shapes. Depending on the column phase, there may be columns specifically designed to work with acids that can help. Stabilwax-DA columns are an example. Derivitization is also used for some compounds to improve peak shapes - fatty acids are often methylated before being analyzed for this reason. Some analysts also do priming injections - injecting high concentration standards to help occupy active sites before doing their analytical injections. There are many options, but they can all have their pros and cons.
Thx you help me alot.