Uric Acid, Blood

Additional Information:

UFHPL Epic order code: LAB141

CPT Code(s):


Collection Procedure:

Serum gel tubes should be centrifuged within 2 hours of collection.

Specimen Requirements:

Type: Peripheral blood


  • Serum, gel
  • Plasma, gel

Sample Volume: 0.5 mL

Stability (collection to time of analysis/testing):

  • Refrigerated: 3 – 5 days
  • Frozen: 6 months
Unacceptable Conditions: Moderate-to-gross hemolysis


Uric acid can be determined by direct measurement, by measurement of oxygen consumed or by measurement ofhydrogen peroxide produced by the uricase reaction. Several methods utilize coupled enzyme reactions to detect the hydrogen peroxide produced by the uricase reaction. Fossati et al1 proposed a method which utilized the well established Trinder reaction to measure the hydrogen peroxide produced, and a substituted phenol to enhance sensitivity. This Uric Acid procedure is a modifcation of the Fossati method. Uric acid is converted by uricase to allantoin and hydrogen peroxide. Hydrogen peroxide reacts with 4-aminoantipyrine (4-AAP) in the presence of N,N-bis(4-sulfobutyl)-3,5-dimethylaniline, disodium salt (MADB) to produce a chromophore which is read bichromatically at 660/800 nm. The amount of dye formed is proportional to the uric acid concentration in the sample.


Within 24 hours

Reference Values:

  • Female: 2.3 – 6.6 mg/dL
  • Male: 4.4 – 7.6 mg/dL