Three methods performed best regarding analytical precision: GC-MS, FPIA
, and HPLC with fluorometric detection using a water-soluble phosphine as reducing agent (TCEP) and SBD-F as fluorescent tag.
The method most commonly used for routinely measuring MTX in clinical laboratories is FPIA
After incubation at 37[degrees]C for 1 hour, total and free apparent digoxin concentrations (in the protein-free ultrafiltrate prepared by centrifuging serum for 40 minutes at 1500g using Centrifree) were measured using the FPIA
7] Nonstandard abbreviations: tHcy, total homocysteine; CVD, cardiovascular disease; MMA, methylmalonic acid; FPIA
, fluorescence polarization immunoassay; GC-MS, gas chromatography-mass spectrometry; MS-MS, tandem mass spectrometry; MTHFR, methylenetetrahydrofolate reductase; CBS, cystathionine 0-synthase; NTD, neural tube defect; and holoTC, holotranscobalamin.
5]; MBHFBA, N-methyl-bis(heptafluorobutyramide); FPIA
, fluorescence polarization immunoassay; DAD, photodiode array detection; HP, Hewlett-Packard; SIM, single-ion monitoring; and HFBA, heptafluorobutyramide.
Mean tHcy values obtained by the FPIA
method (n = 6) were significantly lower at low tHcy concentrations (7 [micro]mol/L) compared with values obtained by HPLC-FD using NaBH4/MBrB and TBP/SBDF as the reduction/ derivatization agents.
A tea was brewed from the leaves and analyzed by FPIA
after cooling to room temperature.
Syva Emit 2000 and Roche "on line" subject to less interference by digoxin-like factors than Abbott TDx FPIA
in newborns and pregnant women.
KCT, antibodies dRVVT) and aCL antibodies Hyperprothrombinemia Prothrombin genotyping Hyperhomocysteinemia HPLC, FPIA
(b) Factor VIII Activity (clotting or amidolytic) or antigen measurement (a) Markers and types of assay listed here represent the authors' choice.