Effect of Increasing Sample Volume

Effect of Increasing Sample Volume

In splitless mode, increasing the volume of the injection increases the amount of sample on the column. But the increase is not linear. If you double the injection volume you will not double the amount of sample on column. The main reason why this happens is the liner cannot hold the entire volume of vaporized sample. Remember, the liner does not have a lid. So injecting more sample will just make more sample flow out the top of the liner. This always happens even with small injection volumes, but the loss of sample becomes exaggerated when large volumes are used.

Effect of Increasing Sample Volume 

Reference - Liner Volumes

Volume = Length x πr2

 HP Liner = 78.5mm x 4.0mm (ID) NOT 6.3mm OD

Volume= 7.85cm x π x 0.2cm2

Volume = 0.986cc or 986 µl

  Varian Liner = 72mm x 4.0mm (ID) NOT 6.3mm OD

Volume= 7.2cm x π x 0.2cm2

Volume = 0.905cc or 905 µl

Subtract approximate amount for glass wool or tapers


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