The details of using luminol 521-31-3 in the formal investigation process cannot be ignored

In the field of criminal investigation, luminol, as an important chemiluminescence reagent, plays a crucial role in detecting potential bloodstains. However, if many details of its use are ignored, it may lead to biased investigation results and even mislead the direction of case investigation. Only by fully understanding and strictly following the details of use can investigators fully utilize the role of luminol in criminal investigations.

Interference from reactions with other substances

1. The effect of bleaching agents: Luminol emits fluorescence in the presence of iron, iron containing alloys, horseradish, or certain bleaching agents. This characteristic may cause problems in crime scene investigation, especially when the scene has been treated with bleach. The chemical components in bleach will react with luminol, causing it to emit strong fluorescence, which will mask the presence of any bloodstains. For example, in some cases of intentional destruction of the crime scene, the suspect uses a large amount of bleach to clean the blood stains. When the investigators use Luminol for detection, they may be misled by the strong fluorescence generated by the bleach, mistaking the scene for no blood stains, thus mistaking important clues.

Luminol powder

2. Interference from animal blood and excrement: Luminol can detect small amounts of blood in animal blood and urine, which may lead to biased test results in some cases. For example, in some houses with pets or houses in rural areas, the presence of animal blood or urine is more common. If these substances are present in the room being tested, the luminol test may show a blood like reaction, causing investigators to mistake them for human blood, wasting valuable investigation time and resources, and even leading the investigation astray. Therefore, before conducting a luminol test, investigators need to collect relevant information from the scene as much as possible, understand whether there are traces of animal activity, and conduct a comprehensive analysis of the test results to avoid drawing erroneous conclusions solely based on luminol test results.

Requirements for testing environment

The use of luminol requires a dark environment because the fluorescence emitted by luminol after reacting with iron ions in the blood is relatively weak and difficult to recognize in bright environments. During the day or in well lit indoor environments, the intensity of ambient light far exceeds that of luminol fluorescence, causing the fluorescence signal to be drowned out and unable to be clearly observed. For example, in some cases that occur at night, if the on-site investigation is conducted during the day, even if there are bloodstains, the fluorescence of luminol may not be detected due to light interference, resulting in the omission of bloodstains. Therefore, investigators usually choose to use luminol for testing at night or by creating a dark environment through shading measures, in order to more accurately detect the location and shape of potential bloodstains and provide important clues for the investigation of the case.  

Grasping the Luminol Luminescence Time

1. Limited luminescence time: Luminol has a limited luminescence time, which requires investigators to take photos and record them as soon as possible. Starting from the reaction between luminol and blood, its luminescence intensity gradually decreases over time. Generally, within a few minutes to a dozen minutes, the fluorescence becomes very weak or even disappears. During this brief time window, investigators need to quickly and accurately record key information such as the distribution, intensity changes, and relationship with the surrounding environment of luminol fluorescence. If the optimal photo recording time is missed, it may result in the loss of important information such as the morphology and location of bloodstains, which will pose difficulties for subsequent case analysis and reconstruction.

2. Techniques and key points for photo recording: When taking photos to record the luminescence of luminol, it is necessary to master the techniques and key points. First, it is necessary to use professional photography equipment to ensure that the camera has high sensitivity and low noise performance, and can clearly capture weak fluorescence signals in low light environments. Secondly, it is necessary to adjust the camera's white balance, exposure time, and other parameters to avoid the photo being too bright or too dark due to improper parameter settings, which cannot accurately reflect the true situation of luminol fluorescence. At the same time, the numbering, labeling, and recording of photos are also crucial in order to quickly and accurately find the required photo materials in the later case sorting and analysis, and improve the efficiency and accuracy of investigation work.

Product packaging

As a manufacturer of chemiluminescence reagents such as luminol, Hubei Xindesheng produces luminol with high purity, strong stability, and high sensitivity, which can play an important role in key fields such as criminal investigation and forensic identification. At the same time, Xindesheng continuously optimizes production efficiency to ensure sufficient supply of goods, whether it is large-scale institutional procurement or small-scale laboratory needs, they can be met in a timely manner. If you have purchasing intentions, please feel free to click on the website for consultation at any time!