General Product Information: Free PSA (fPSA) is isolated from human seminal fluid and is supplied as a liquid in 10mM Tris, 0.1% Sodium Azide, pH 8.0 ± 0.1. The non-complexing form is purified from material used to prepare the PSA-ACT Complex. The protein concentration for P0723 is determined by immunoassay. The protein concentration for other forms is determined by A280 using an extinction coefficient of 1.86 (Emg/ml = 1.86). Both of the complexed forms are prepared by in-vitro complex formation with the purified proteins. PSA-ACT complex is supplied as a liquid in 10mM Sodium Acetate, 150mM Sodium Chloride, 0.1% Sodium Azide, pH 5.6 ± 0.1. The protein concentration is determined by A280 using an extinction coefficient of 1.0 (Emg/ml = 1.0). PSA-A2M is supplied as a liquid in 20mM Sodium Phosphate, 150mM Sodium Chloride, 0.05% Sodium Azide, pH 7.4 ± 0.1. Protein is determined using the Bradford method (BSA standard).
Catalog No. P0723 (Part No. 90015) - fPSA
Purity: ≥ 40% by SDS-PAGE
Concentration: ≥ 1.0 mg/ml by immunoassay
Sample Certificate, MS Word
Catalog No. P0724 (Part No. 90016) - fPSA
Purity: ≥ 95% by SDS-PAGE
Concentration: ≥ 1.0 mg/ml by A280
Sample Certificate, MS Word
Catalog No. P0725 (Part No. 90017) - fPSA
Purity: ≥ 99% by SDS-PAGE
Concentration: ≥ 1.0 mg/ml by A280
Sample Certificate, MS Word
Catalog No. P0715 (Part No. 90049) - fPSA, lyophilized
Purity: ≥ 99% by SDS-PAGE
Concentration: ≥ 1.0 mg/ml by A280 prior to lyophilization
Sample Certificate, MS Word
Catalog No. P0624 (Part No. 90010) - PSA-ACT complex
Purity: ≥ 95% by SDS-PAGE
Concentration: ≥ 1.0 mg/ml total protein by A280
PSA Content: 30-70%
(ratio of PSA by immunoassay/Total Protein by A280)
Sample Certificate, MS Word
Catalog No. P5824 (Part No. 90232) - PSA-A2M complex
Purity: Reported by SDS-PAGE and Western Blot
Concentration: Determined by the Bradford method (BSA standard)
Contaminants: Free A2M estimated using a trypsin inhibition assay
Sample Certificate, MS Word
Catalog No. P5125 (Part No. 90024) - noncomplexing fPSA
Purity: ≥ 98% by SDS-PAGE
Concentration: > 0.5 mg/ml by A280
Activity: < 7.0 units/mg by chymotrypsin enzyme assay
Sample Certificate, MS Word
Prostate Specific Antigen (PSA), a glycoprotein of the glandular kallikrein family, is a serine protease with chymotrypsin-like enzymatic activity. It has a molecular weight of approximately 33,000-34,000 Da and is found primarily in prostate tissue and seminal fluid. Serum levels of PSA are very low in healthy individuals (0 - 4 ng/ml), but are often elevated in malignant and benign prostatic disease. As such, immunoassays for serum levels of PSA have proven useful in the diagnosis and follow-up of prostate cancer.
PSA released into circulation is present as unbound, free PSA (fPSA) or bound to serum protease inhibitors, such as α1-antichymotrypsin (ACT) and α2-macroglobulin (A2M). Research indicates that immunoassays for serum levels of PSA alone cannot be relied on to distinguish prostate cancer from benign prostatic hyperplasia (BPH). Serum levels of PSA-ACT complex are reportedly higher in patients with prostate cancer than in those with BPH. As such, measuring the ratio of PSA-ACT to fPSA in patient samples is proving valuable in the differential diagnosis os prostate cancer. In addition, immunoassays for PSA-A2M serum levels may prove valuable in prostate cancer diagnosis, but further study is required.
Note: Monoclonal and Polyclonal Antibodies are available for PSA.