I am trying to calculate the fatty acid content in g/100g seaweed on FID but I am unsure which formula to use.
We use C17:0 FFA as internal standard.
Other information we have is:
Volume of the internal standard = 50 uL of 1 mg/ml solution
Sample mass: 100 mg seaweed
Extracting with 4 ml of a 2% H2SO4 methanol solution and 2 ml chloroform (direct transesterification)
After transesterification we add 1 ml 0.9% saline and further extract FAMES 3 times with 2 ml hexane each time.
Thereafter the hexane is evaporated.
Then the FAMES are reconstitute with 200 ul isooctane, 1 uL injected with a 1:10 split.
I hope this information suffices.