Editorial Note: The findings in this report indicate that the fully automated FPIA
assay performed best with respect to lowest interlaboratory variation, analytical precision, and apparent analytical bias relative to a GC-MS method.
10]-methylpteroic acid; FPIA
, fluorescence polarization immunoassay; LC-MS/MS, liquid chromatography-tandem mass spectrometry.
When the aliquots of drug-free serum pool were supplemented with Asian, American, and Indian ginsengs, significant apparent digoxin concentrations were observed using the FPIA (range, 0.
We observed statistically significant increases in serum digoxin concentrations in the presence of various ginsengs when FPIA was used.
Because of the small number of laboratories included in each method for each of the surveys, the within-method variation data must be interpreted with caution; however, the FPIA method performed in surveys 2 and 3 consistently had lower CVs (mean, 5.
At 33 [micro]mol/L tHcy, values obtained by the FPIA method were significantly lower (P = 0.
Digoxin-like immunoreactive substance: monoclonal and polyclonal RIA and FPIA
We report the observation of false-positive results obtained with the AxSYM (r) FPIA
Amphetamine/Methamphetamine II assay (Abbott), which is widely used to detect commonly abused amphetamine compounds in human urine.
To rule out the possibility that the observation of higher MEGX concentrations in uremic subjects was an artifact attributable to cross-reactivity with the TDx FPIA
by other lidocaine metabolites that may have accumulated in such patients, we compared the results of the FPIA
with those of a highly specific HPLC method in three healthy volunteers and three patients with severe renal dysfunction.