2.5.2 Linearity
Blank serum and CSF (180 μL) were added with 20 μL gradient standard
solutions at concentrations of 0.05, 0.2, 0.5, 1, 2, 5, 10 and 20 μg/mL
respectively to make the TGC content of serum and CSF at the
concentration of 5, 20, 50, 100, 200, 500, 1000 and 2000 ng/mL.