Forensic Analysis of Blood using Luminol. Luminol. Redox reaction with oxygen in the presence of catalyst produces a bright blue glow. Used in forensic analysis for detection of blood Iron in hemoglobin acts as catalyst Other common catalysts Biological: copper and cyanide
2H2O2 O2 + 2H2O
2 H20 +
Triplet Dianion(excited state)
*intersystem crossing is radiationless transition between different states of spin multiplicity
As shown by the red dot, Luminol is excited into the triplet dianion state chemically. Through intersystem crossing, the molecule is able to transtion into the singlet dianion state of the same energy. Finally, the molecule fluoresces from the singlet dianion state to the ground state dianion emitting a photon of energy hv.