An Improved Colorimetric Assay for Pyridoxal Phosphate Using Highly Purified Apotryptophanase

  • Betty E. Haskell


Methods for the analysis of pyridoxal phosphate, the principal cofactor form of vitamin B-6, have achieved new importance with the demonstration that levels of the coenzyme in serum constitute a useful test of vitamin B-6 nutritional status (1). Enzymic assays are among the most satisfactory for measuring pyridoxal phosphate in biological samples for several reasons: 1) they are highly specific, 2) they permit quantification of pyridoxal phosphate at the level of 10−11 moles, and 3) the analyses work well in crude biological extracts without prior isolation or purification.


Ammonium Sulfate Pyridoxal Phosphate Potassium Dihydrogen Phosphate Sulfinic Acid Pyruvate Formation 
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Copyright information

© Springer Science+Business Media New York 1981

Authors and Affiliations

  • Betty E. Haskell
    • 1
  1. 1.Department of Home EconomicsUniversity of TexasAustinUSA

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