ADA Test Kit

The Adenosine Deaminase (ADA) Test Kit (PNP-XOD Method) is a diagnostic reagent used for the direct quantitative determination of Adenosine Deaminase (ADA) activity in human serum, plasma, or cerebrospinal fluid (CSF). Here are the key details about this test kit:

• Principle:
  • The ADA assay is based on the enzymatic deamination of adenosine to inosine, which is further converted to hypoxanthine by purine nucleoside phosphorylase (PNP).
  • Hypoxanthine is then converted to uric acid and hydrogen peroxide (H₂O₂) by xanthine oxidase (XOD).
  • H₂O₂ reacts with N-Ethyl-N-(2-Hydroxy-3-sulfopropyl)-3-methylaniline (EHSPT) and 4-aminoantipyrine (4-AAP) in the presence of peroxidase (POD) to generate a quinone dye, which is monitored kinetically.
• Clinical Significance:
  • ADA is an enzyme widely distributed in mammalian tissues, particularly in T lymphocytes.
  • Increased ADA levels are found in various forms of tuberculosis, making it a marker for the disease.
  • ADA levels can also increase in infectious mononucleosis, typhoid, viral hepatitis, initial stages of HIV, and certain malignant tumors.
• Reagents Composition:
  • Enzyme Reagent -1 (R1):
    • Tris-HCl pH 8.0
    • 4-Aminoantipyrine (4-AA)
    • PNP (Purine Nucleoside Phosphorylase)
    • XOD (Xanthine Oxidase)
    • Peroxidase
  • Substrate Reagent -2 (R2):
    • Tris-HCl pH 4.0
    • Adenosine
    • TOOS (N-Ethyl-N-(2-Hydroxy-3-sulfopropyl)-3-methylaniline)
• Storage and Stability:
  • Reagents are ready to use and stable up to the expiry date when stored at 2-8°C.
  • On-board stability is 1 month at approximately 2-8°C.
• Sample/Specimen and Storage:
  • Serum or heparinized plasma may be assayed.
  • Venous blood should be collected and handled anaerobically.
  • Do not use citrate or oxalate as an anticoagulant.

Remember that interpreting ADA results should be done in consultation with your healthcare provider to assess overall health and specific conditions.