2.5.4 Extraction recovery and matrix effect
The extraction recovery of TGC in serum and CSF was evaluated by
comparing the peak area obtained from the blank serum and CSF spiked
with analyte at low, medium and high concentrations with which obtained
from standard solutions. Blank serum and CSF was processed as stated and
then spiked with standard solution at low, medium and high
concentrations to assess the matrix effect. The ratio of peak areas of
TGC from spiked serum and CSF samples and pure TGC solution was defined
as the matrix effect.