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Published on: January 28, 2013
Quantitation of total biopterin and tetrahydrobiopterin in plasma
Durk Fekkes1, Ans Voskuilen-Kooijman
1Department of Neuroscience, Laboratory of Neurobiology, Room Ee 1438, Erasmus MC, P.O. Box 1738, 3000 DR Rotterdam, The Netherlands. d.fekkes@erasmusmc.nl
Objective:
To develop a reliable method for the determination of tetrahydrobiopterin and total biopterin in plasma.
Methods:
Modifications include blood collection and handling procedures.
Results:
Collection of blood in the presence of 0.1% (w/v) dithiothreitol and waiting for 2-3 h before centrifugation are optimal for adequate quantitation of both pterins.
Conclusions:
For a reliable determination of tetrahydrobiopterin and total biopterin in plasma, blood tubes must contain a dimercapto-antioxidant and time between blood collection and centrifugation is critical.
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