Advantages, disadvantages and usage of the murder-seeking reagent luminol
Luminol, also known as the chasing reagent, is also known as luminol. In the 1830s, German crime scene identification experts inadvertently discovered that luminol would produce fluorescence when it came into contact with blood. Western countries responded to this luminescence. The mechanism has been studied in depth. So far, luminol reagent has become a commonly used reagent in bloodstain investigation.
The luminescence principle of luminol is similar to the fluorescence reaction in fireflies. In an alkaline solution, it can undergo an oxidation reaction with metal catalysts such as iron and copper, thereby releasing energy in the form of photons, resulting in fluorescence. It can be seen that metal catalysts play a key role in the process of luminescence reaction. The content of metal catalysts determines the intensity of fluorescence, and there is heme in human blood, which contains iron that can play the role of metal catalysts. Therefore, When blood and luminol reagent come into contact, fluorescence is generated, which is the fate of luminol and blood.
Advantages of Luminol
1. High sensitivity, blood stains can still be detected after many years, even many times of washing, and dilution by 10,000 times is useless for luminol.
2. The configuration method is simple and easy to operate, and the luminol reagent is relatively stable and easy to store.
3. Luminol is less harmful to the human body and is relatively safe for those who often do experiments or on-site surveys.
Disadvantages of Lumino
Luminol can be affected by other oxidizing agents. In addition, when using Luminol, it is formulated as a solution. The solution can cause potential bloodstains to become blurred, further diluting the already diluted bloodstain and destroying the shape of the bloodstain. , which will make genetic blood testing of blood more difficult, and will also make it more difficult to judge the case by the shape of the bloodstain. In any case, luminol is still a commonly used reagent in bloodstain detection.
The use of luminol in criminal investigation
The luminol reagent used to detect blood stains is generally composed of: 0.1g luminol, 5g sodium carbonate, 100ml distilled water and 6ml 30% H2O2 solution into a well-sealed spray can, and the configuration can be completed. When using, pay attention to the need to close the doors and windows of the scene, cut off all the power, so as to avoid visual interference of other light sources to the fluorescence of the luminol reaction. Generally speaking, the light-emitting time is 30 seconds, so you must seize the time, take pictures quickly, and pay attention when taking pictures. Details such as luminous point position, luminous shape, brightness distribution, etc.
Desheng Biochemical was established in 2005, dedicated to the research and development and production of blood collection tube reagents, chemiluminescence reagents, in vitro diagnostic reagents and biological buffers. The products are not only sold in China, but also exported to overseas. Due to their excellent and stable quality, they are deeply loved by customers, with good feedback and high repurchase rate.
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