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interfere with metabolic assays based on tetrazolium
References
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Conclusions
The reduction of NBT to formazan by FA and
other amino acids is described in this article. The
reduction, which involves only one of the two tetra-
zolium rings of NBT, is considerably more rapid with
folic acid and N-(4-aminobenzoyl) glutamic acid than
with the other amino acids examined. The electron-
donor moiety appears to be the carboxylic acid in
the alpha position. The relatively high concentrations
(millimolar) of amino acids present in cell samples and
in vitro biological systems such as cell culture media
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Acknowledgements. This work was funded by the CARIPLO
Foundation, Project no. 2009-2440 ”Development and safety
assessment of nanostructured compounds applicable to boron
neutron capture therapy”. We wish to thank Dr Federica
Corana (Centro Grandi Strumenti, University of Pavia) for
the mass spectrometry analysis.