Background: Immunoradiometric assay is one of
the most common and precise methods for
determination of prostate specific antigen (PSA) in
clinical laboratories. Usual use of human serum in
routine assays has many disadvantages such as easy
contamination and precipitation, instability and
unavailability. Thus in order to avoid these problems
the artificial matrix was used which acts similar to
human serum. Materials and Methods: In order to
design immunoradiometric assay for prostate specific
antigen, series of standards in different concentrations
were needed for special artificial matrix preparation.
The influence of artificial matrix in standards was
studied to determine prostate specific antigen in
comparison with human serum. Some different
factors, such as the amount of non-specific bonding
(NSB), precision, and accuracy, conditions of storage
and stability of these standards prepared by artificial
matrix were investigated. Results: The most
appropriate artificial matrix (Tris-glycine (25.0 mmol/L)
+ NaCl (75.0 mmol/L) + Tris (12.5 mmol/L) +Triton X-
100 (0.5 ml/L) + HSA (1.2 g/L) + Urea (0.5 mol/L)) for
preparing the standards was selected in comparison
with human serum (HSA) and a commercial kit
standards. HSA and Urea concentration have more
critical influences on the properties of the standards.
The amount of NSB of the selected matrix was the
lowest one, so the selected matrix was the most
suitable for preparing the standards. The results show
the optimum condition of storage duration of our
standards for one year was in refrigerator (2-8°C). It
was observed that preparation of standards with
selected matrix had acceptable accuracy and
precision. Conclusion: According to the results,
standards which were prepared with this matrix had
suitable and appropriate properties and it could be
utilized to prepare PSA standards in
immunoradiometric assay. Iran. J. Radiat. Res., 2008 6 (1):
51-58
Foroutan H, Najafi R, Babaei M, Shafii M. Preparation of prostate specific antigen standards for immunoradiometric assay. Int J Radiat Res 2008; 6 (1) :51-58 URL: http://ijrr.com/article-1-379-en.html