Quantitation of red blood cell folates by stable isotope dilution gas chromatography-mass spectrometry utilizing a folate internal standard.
Santhosh-Kumar CR, Deutsch JC, Hassell KL, Kolhouse NM, Kolhouse JF. Quantitation of red blood cell folates by stable isotope dilution gas chromatography-mass spectrometry utilizing a folate internal standard. Anal Biochem. 1995 Feb 10; 225(1):1-9.