Prostate Specific Antigen (PSA) ELISA for serum or plasma 2-25ng/ml Dialab

In recent years the determination of serum prostate specific antigen (PSA) has become the most accepted method to improve the diagnostic specificity of digital rectal examination (DRE). Although PSA is a tissue specific protein and not solely tumour specific it has become the most important marker for prostate carcinoma showing a better specificity than other biochemical markers used in this context such as Total alkaline phosphatase, carcinoembryonic antigen etc.

In 1979, Wang et al isolated a specific antigen for normal prostate tissue and called this protein PSA. As demonstrated by immunohistological studies, PSA is localised in the cytoplasm of prostate acinar cells, ductal epithelium and in the secretion of the ductal lumina, present in normal, benign hyperplastic and malignant prostate tissues as well as metastatic prostate cancer and in seminal plasma. If the structural integrity of the prostate is disturbed and/or the gland size is increased, the amount of PSA in the blood plasma may become elevated. An elevation of PSA levels to values higher than 3-4 ng/ml has been reported for patients with either benign prostatic hypertrophy (BPH) or prostate carcinoma. At this threshold follow-up examinations that allo9w differentiation between these two conditions are recommended.

The determination of serum PSA levels is not only important for the screening of patients for disease but also for monitoring patients that have been treated, Having regular PSA measurements are an important tool to examine the potential and actual effectiveness of surgery of other therapies. An increase in PSA after radical prostatectomy or radiotherapy ay allow earlier discovery of residual or recurrent carcinoma.

This assay is intended for the quantitative determination of PSA in human serum or plasma for diagnostic use. This 96 well ELISA can provide up to 40 patient tests. The test wells are coated with an antibody directed towards and epitope of an antigen molecule. An aliquot of patient serum is incubated in the coated well together with enzyme conjugated antibody directed to a different region of the antigen molecule. After incubation the unbound conjugate is washed off. The amount of bound conjugate is proportional to the concentration of antigen in the sample.

Antibody coated Microtiter wells : 12x8 well strips
Zero Calibrator/Sample diluent: 1x10ml
Calibrator set: 5x0.5m (1.56, 3.12, 6.25, 12.5 and 25 ng/ml)
Controls, High & Low: 2x0.5ml
Enzyme Conjugate : 1x12ml
TMB Substrate Solution : 1x12ml
Stop Solution: 1x14ml
Sample volume: 25µl human serum or plasma to be run in duplicate
Incubation time: 85 minutes (5 min,60 min, 20 min. All at room temperature)
Calibration range: 0 – 25.0 ng/ml
Sensitivity: 0.2ng/ml
Store at 2-8°C.