Question
| A. |
Barberio’s test |
| B. |
Acid phosphatase test |
| C. | Florence test |
| D. |
Tiechman’s test |
|
Correct Answer � A Explanation |
 |
Tests for Seminal Stains
The Barberio’s test is a microscopic test used to identify the presence of sperm. It employs picric acid and when the stain is allowed to react with picric acid it leads to the formation of yellow needle shaped spermine picrate crystals, including the presence of seminal stain
Florence Test: Florence test identifies the presence of spermine in seminal stains by forming characteristic needle-shaped crystals of spermine phosphotungstate when mixed with Florence reagent (a solution of potassium iodide and iodine in water).
Acid Phosphatase Test: This test detects high levels of acid phosphatase enzyme present in seminal fluid. The presence of acid phosphatase causes a color change when reacted with substrates like sodium alpha-naphthyl phosphate and Fast Blue B.
Creatine Phosphokinase Test: This test identifies the enzyme creatine phosphokinase (CPK) in seminal stains, which is present in high concentrations in semen. Elevated levels of CPK can confirm the presence of seminal fluid.
Immunological Test to Detect Prostate-Specific Antigen (PSA): Immunological tests for PSA use antibodies specific to PSA to detect its presence in seminal stains, providing a sensitive and specific method to confirm the presence of semen.
Tests for Blood Stains
Benzidine Test:The benzidine test detects the presence of hemoglobin in blood stains. When benzidine reagent is applied to a suspected blood stain, the presence of hemoglobin catalyzes a reaction producing a blue color.
Phenolphthalein (Kastle-Meyer) Test:This presumptive test for blood uses phenolphthalein and hydrogen peroxide. In the presence of hemoglobin, the phenolphthalein turns pink, indicating a positive result for blood.
Takayama Hemochromogen Crystal Test:This confirmatory test for blood involves adding pyridine and glucose to a blood stain. The formation of pink, feathery hemochromogen crystals under a microscope confirms the presence of blood.
Teichmann’s Hemin Crystal Test: In this test, blood is treated with glacial acetic acid and heated to form characteristic brownish-yellow hemin crystals (Teichmann crystals), which are indicative of the presence of blood.
Spectroscopic Test: The spectroscopic test identifies blood by analyzing the absorption spectrum of hemoglobin and its derivatives. Characteristic absorption bands confirm the presence of blood, providing a specific identification method.
