Free hemin results from the breakdown of hemin-containing proteins such as hemoglobin and myoglobin. It can be detected in various body fluids such as saliva, urine and csf under various pathological states. Free hemin exists in cells at a very minute concentrations (< 1µM ≈ 650 ng/ml) exerting regulatory functions such as repression of nonspecific δ-aminolevulinate synthase expression and induction of microsomal hemin oxygenase-1. Hemin can stimulate growth of oral bacteria involved in gingivitis and is an indicator of possible pathological conditions when found in the urine or feces. BioVision’s Hemin Assay Kit utilizes peroxidase activity in the presence of hemin to provide a simple, exquisitely sensitive assay which causes the conversion of a colorless probe to a strongly colored (λ = 570) compound. Trace amounts of Hemin can be quantitated in the 5-160 pg (10-250 fmol) range.