[kate71]

Hi there,

for the analyse of X a soxhlet extraction is carried oud. The problem is that I get low extraction recovery (around 20%) when I spike samples at low level. The higher the level I spike the higher the extraction recovery is until it gets 100% (then it remains stable at 100% recovery extraction). This trend is completely lineal, r2=0.995

Why do I get so low extraction recoveries? Why is it lineal?

Thanks in advance

[marquis]

I can only make a guess.

Is it possible that the standard is adsorbing on to the
material in the extraction thimble?