|Values are valid only on day of printing.|
100 mcL of urine is spiked with d8-homocystine (2 nmoles) added as internal standard. After specimen reduction and deproteinization, the analysis by tandem mass spectrometry is performed in the multiple reaction monitoring mode.(Magera MJ, Lacey JM, Casetta B, Rinaldo P: A method for the determination of total homocysteine in plasma and urine by stable isotope dilution and electrospray tandem mass spectrometry. Clin Chem 1999;45:1517-1522)
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