Luminol in the forensic science

Abstract

In a crime scene, the collection of evidence and a subsequent laboratory analysis compose the fundamental steps to allow the expert to reveal the truth for the final verdict in a jury and to bring back the comfort to the victim’s family. Bloodstains are usually found and sent to laboratories as a vestige to unravel the origin of the material. However, some scenes are modified in order to conceal the real culprit for the criminal act. For these cases, the luminol reagent can be useful. This test is very often used to visualize occult blood. Luminol is considered the most sensitive test once it can identify the blood presence in scale of nanograms. When this reagent comes into contact with blood,the light emission occurs through a phenomenon known as chemiluminescence. This luminescence can be produced by other interfering compounds, leading to a misinterpretation for the presence of blood. Despite this shortcoming, the present review article highlights the indispensability of the reagent luminol on a crime scene.

In-SilicoInvestigation of Luminol, Its Analogues and Improved Mechanism of Chemiluminescence for Blood Identification Beyond Forensics

“…The gap in knowledge could be traced to an oversight in taking into cognizance that heme in the hemoglobin is not just an iron (II) ion but a biological multi-oxidative state iron complex that can be degraded by oxidation. Heme comprise of iron (II) which binds to the center of the porphyrin IX by covalent and coordinate bonding (da Silva et al, 2012). Study has shown that peroxidase-like activity of heme-like compounds called Prussian blue nanoparticles (PBNPs) was higher than that of Fe (III) and that the catalytic capacity of PBNPs did not simply originate from the Fenton reaction (Chen et al, 2018).…”

Ultrasound-Enhanced Chemiluminescence for Bioimaging

“…This compound possesses a superoxide anion in its structure, which is responsible for causing coelenterazine to give out CL. Unlike luminol, coelenterazine does not require any catalyst to trigger CL (Silva et al, 2012). CLA (2-methyl-6-phenyl-3,7-dihydroimidazo[1,2-a]pyrazin-3-one) and specifically MCLA probe (2-methyl-6-(4-methoxyphenyl)-3,7-dihydroimidazo[1,2-a]pyrazin-3-one) which is more efficient are some of the several coelenterazine analogs that have been prepared and used (Dubuisson et al, 2005;Wang et al, 2012;Diaz et al, 2018).…”

Lumonil Compounds in Criminal Chemistry (A review part I)

“…In short, along with the synthesis of many lactic derivatives that reduced the synthesis of chemical luminol and did not change the maximum emission wavelength, then measured the basic physical properties of luminol and diphthalateamipin, and found that the results shown through the search is identical with theoretical calculations. Two types of chemiluminescence, Fluorescence and Phosphorescence [16,17].…”