Order Code LABGOR, B6PA Pyridoxic Acid, Plasma
Additional Codes
Mayo Test Code: B6PA
Method Name
Only orderable as part of a profile. For more information see B6PRO / Vitamin B6 Profile (Pyridoxal 5-Phosphate and Pyridoxic Acid), Plasma.
Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS)
Reporting Name
Pyridoxic Acid (PA), PSpecimen Type
Plasma HeparinShipping Instructions
Ship specimen in amber vial to protect from light.
Specimen Required
Only orderable as part of a profile. For more information see B6PRO / Vitamin B6 Profile (Pyridoxal 5-Phosphate and Pyridoxic Acid), Plasma.
Patient Preparation:
1. Patient should fast overnight (12-14 hours); infants-should have specimen collected before next feeding. Water can be taken as needed.
2. For 24 hours before specimen collection, patient must not take multivitamins or vitamin supplements.
Supplies: Amber Frosted Tube, 5 mL (T915)
Collection Container/Tube: Green top (sodium or lithium heparin) or plasma gel separator (PST)
Submission Container/Tube: Amber vial
Specimen Volume: 1 mL
Collection Instructions:
1. Centrifuge at 4° C within 2 hours of collection.
2. Aliquot all plasma into amber vial and freeze immediately.
Specimen Minimum Volume
0.75 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Plasma Heparin | Frozen | 29 days | LIGHT PROTECTED |
Reference Values
Only orderable as part of a profile. For more information see B6PRO / Vitamin B6 Profile (Pyridoxal 5-Phosphate and Pyridoxic Acid), Plasma.
3-30 mcg/L
Performing Laboratory

CPT Code Information
82542
Useful For
Determining the concentration of pyridoxic acid in the assessment of vitamin B6 status
Reject Due To
Gross hemolysis | OK |
Gross lipemia | OK |
Gross icterus | OK |
Method Description
The stable isotope pyridoxal 5-phosphate-d2 and/or pyridoxic acid-d2 is added to plasma as an internal standard. Meta-phosphoric acid solution is then added to precipitate the proteins. Following sedimentation of the proteins, an aliquot of the clarified supernatant fluid is subjected to separation of pyridoxal 5-phosphate, pyridoxic acid, and internal standards from other plasma components by reverse-phase high-performance liquid chromatography with quantitation by tandem mass spectrometry.(Unpublished Mayo method)
Day(s) Performed
Monday through Thursday, Saturday, Sunday