Running samples simultaneously on GC-TQ and GC-FID

I have recently procured a GC-TQ with FID (8890 and 7000E) with two separate autosamplers for analysing blood samples. I am facing challenges with sample volume, preferring to inject from the same vial simultaneously into both the FID (front inlet) and MS (back inlet) or MS/MS. While there's a dual injection option available, it requires two vials, which is not ideal for my workflow (460 samples waiting!). I am seeking assistance with setting up a sequence in MassHunter software to use one vial but two inlets, allowing me to run samples together. Is this possible? We have one oven with two columns, one for the FID and one for MS. 

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  • Lance's suggestions are sound.

    What does the FID gain you?  Have you thought of running the QQQ in MRM/Scan mode so that you can get the MRM data along with a scan total ion chromatogram?  

  • We are doing FAMEs and use the FID for routine work as we have a high volume of samples. We are working towards the MRM but we are not there yet. In the mean time we are using the MS, however this brings another question. For some reason, when running the same sample on FID and MS simultaneously the FID data is two minutes behind the MS data. Same conditions, same oven, flow, lengths of columns etc. Is there a way this can be fixed? 

  • The MS column exits into vacuum.  The FID column exits to atmospheric pressure.

    Same carrier gas, column, oven temperature, inlet pressure results in different holdup times.  These examples are using the Pressure Flow Calculator available here GC Calculators and Method Translator Software | Agilent   and also in the GC parameters page in MassHunter Acquisition.

    FID                                                                                                                 MS

        

    There are some ways to get the retention times to an MS and to an FID closer, but close across the entire oven profile is quite difficult.

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  • The MS column exits into vacuum.  The FID column exits to atmospheric pressure.

    Same carrier gas, column, oven temperature, inlet pressure results in different holdup times.  These examples are using the Pressure Flow Calculator available here GC Calculators and Method Translator Software | Agilent   and also in the GC parameters page in MassHunter Acquisition.

    FID                                                                                                                 MS

        

    There are some ways to get the retention times to an MS and to an FID closer, but close across the entire oven profile is quite difficult.

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