A modified reagent for the confirmation of blood
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Dried Blood Spots - Preparing and Processing for Use in Immunoassays and in Molecular Techniques
Published on: March 13, 2015
1Tucson Police Department, AZ.
Journal of Forensic Sciences
|November 1, 1993
Abstract:
Oxygen and pyridine compete for the same binding site on the heme molecule. Lowering the oxygen concentration in Takayama's reagent by addition of an oxygen scavenger such as dithiothreitol (Cleland's reagent) shifts this equilibrium in favor of pyridine, and increases the rate at which hemochromogen crystals are formed. This modification makes the confirmatory test for blood faster, and therefore easier to use. The absolute sensitivity and the specificity of the reagent appear unchanged.

