Brentamine Fast Violet B Test
Definition
A two-component spot test in which sodium alpha-naphthyl phosphate (substrate) is hydrolysed by AP to alpha-naphthol, which couples with fast violet B diazonium salt to produce a purple-violet azo dye. A strong colour change within 30 seconds is presumptive positive for semen.
Related terms
- Acid Phosphatase (AP)
- An enzyme present at high concentrations in seminal plasma. The Brentamine Fast Violet B (or SERI AP) spray test detects acid phosphatase...
- False Positive
- A test result that indicates the presence of a target analyte when it is absent. In forensic serology this may mean incorrectly...
- Fluorescent AP Assay
- A more sensitive format using 4-methylumbelliferyl phosphate (4-MUP) as substrate. AP cleaves 4-MUP to 4-methylumbelliferone, which fluoresces under UV. Useful on aged...
- Prostatic Acid Phosphatase (PAP)
- The AP isoform secreted by acinar epithelial cells of the prostate gland, found in seminal plasma at concentrations of 25-1,000 U/mL, orders...
- Quantitative AP Threshold
- A numerical activity level, expressed in units per litre of extract, above which a result is treated as semen-positive. Common thresholds range...
Explained in
- Acid Phosphatase Screening for SemenA two-component spot test in which sodium alpha-naphthyl phosphate (substrate) is hydrolysed by AP to alpha-naphthol, which couples with fast violet B diazoniu...